Bizarre, Arcane, and Weird Magic

Swords and Daggers

Dagger of Disease (Dagger +1): This peculiar yet vicious weapon gives the victim a deadly disease, on a roll of 19 or 20, that causes one hit point of damage every turn unless a successful saving throw is made versus death magic. Only a cure disease can get rid of the ailment. Note this weapon does not afflict paladins or any others (unicorns etc.), who are immune to disease.
Dagger of Stupidity (Dagger -2): This cursed item decreases the users INT score by 1d6 points (predetermined and remains the same throughout the item's existence). This affliction can be removed by remove curse or wish. After it is removed, the player regains 1 point of Intelligence lost per every 2 days.
Loremaster: An intelligent dagger (+3) named Loremaster, Lorey to his friends, (Al LG Int 17 Ego 20 Legend Lore 1/week, Esp 3/day, detect magic at will. Languages: common, elven, orcish, dwarvish, frost giant. Loremaster is a very snooty weapon given to pouting whenever he doesn't get his way and speaking out to show his obvious intelligence whenever possible. Loremaster loves to read and will be insistant upon it's owner buying him history and alchemical texts all the time. He does not generally like to be used in combat, because parrying weapons gives him a headache; however, he will come to aid if necessary, flying from his sheath to attack foes unmercifully. Loremaster is very jealous when it comes to his owner, although he knows they can never be together physically, he quotes poetry to to the owner constantly and can't stand an owner with another intimate companion.
Goblin Blade (Shortsword +1): This green, crude looking shortsword will, upon, a successful roll of 20, turn their opponent into a goblin (See Monstrous Manual). This affliction can only be cured by a remove curse or wish or similar magic.
Sword of Dismemberment (Longsword +3): This fearsome longsword is the twisted cousin of the Vorpal Blade (see DMG), but instead of severing the head from the body, it severs a particular limb if the user gets a 20 or better (with modifier) on their combat roll. To find out which limb see table below. Note: For every limb severed, the victim loses 10% (rounded down) extra non-healable hit points of damage. Creatures that regenerate do not lose hit points permanently (assuming they don't die) 1d20 Roll: 1-7 = Right arm. 8-14 = Left arm. 15-17 = Right leg. 18-20 = Left leg
Wooden Sword (Shortsword +2): This shortsword made of enchanted wood passes through all non-magical metal as if it did not exist. Therefore all metal armors to not count in the opponents armor class. This special wood is immune to normal fires. It can instantly be destroyed by warp wood.

Piercing Weapons

Arrow of Slaying: Psionics (Arrow +3): This item is identical to the ones mentioned in the DMG, but only it affects psionics.
Bow of Strength: This common-looking short bow is actually an incredible weapon. With a check versus STR with a -5 modifier, a character can shoot an arrow through an opponent and into anything behind it. Against the first target the arrow does normal damage +1d12, and against the second target, does just normal damage. The arrow is, of course, totally unre-useable.
Crossbow of Accuracy: This weapon subtracts one to three (1d6/2) to the users THAC0 (calculated before it is found). Otherwise, it does normal damage. This weapon does not radiate any form of magic, as it is a weapon of precise making, not magical.
Darts of Detonation (Dart +2): Normal looking darts, except that after a successful hit, the dart will explode in 1d4-1 rounds (zero rounds meaning instantaneous), and do 1d8+2 points of damage. If removed before it detonates, it will not discharge. Afterwards, treat as a normal dart in damage. These darts can also be used against doors and such (item saving throws apply).
Trident of Dehydration (Trident +3): This aqua-blue trident has the vicious ability to absorb water from it's opponents. This does normal damage plus 2d4 damage land based creatures and 2d10 in amphibious and water-based creatures. Victims must drink water within one turn or pass out. The weapon automatically kills water elementals on a successful hit (saving throw vs. death magic does apply). It will also absorb one gallon of normal or holy water every 2 rounds if it is standing, like in a pond or puddle (Max. 10 gallons every 24 hours). Unholy water renders the trident non-magical, and thereafter a normal weapon. Note: This weapon is not strong enough to absorb running water.

Bludgeoning Weapons

Diamond Mace (Mace +3): This very expensive weapon has diamond tips on the head of the mace. This allows the attacker to hit his opponent as if he were two Armor Classes lower (maximum of 10), due to the extreme sharpness of the weapon. Each diamond is about 100 gp in value, but can be worth much more if left in the weapon due to the difficulty in mounting the gems in the steel mace head.
Flail of Disenchantment (Flail +2): This great weapon, when used to successfully parry, disenchants any magical weapon (Use item saving throws). Thereafter, that weapon is a normal weapon, but loses all pluses and special benefits. Nothing short of a wish can bring it's abilities back. However, this weapon does not have a disenchanting effect on intelligent weapons with egos of 10 or higher. It has no special effect on magical armors.
Flail of Punishment (Special): This weapon does absolutely NO damage. Instead, it inflicts unimaginable pain, which is only in the victims mind. Designed to torture but not kill. Appears as one nasty flail (Something on the order of cat o' nine tails). Victim may attempt to disbelieve the "illusion" of pain versus INT-6. DM's discretion on the victim being able to keep any secrets or confessions (ex: Save versus CON).
Mace of Lightning (Mace +2): This mystical weapon stores the power of lighting within it. Each charge delivers 1d8 points of damage. Carries 1d4 charges. To recharge, it must be struck by lightning. Also it may be used to absorb lightning attacks, and thus recharging the mace one charge. When struck by lightning, the holder is not affected by the attack. Acts as a normal mace when used against creatures immune to lightning (+2 does not apply). Stuns water elementals for 1d4 rounds.
Ruby Mace (Mace +2): This mace is very similar to the diamond mace (mentioned above). But this weapon makes the opponents armor class one class lower, instead of two.
Warhammer of Stunning (Warhammer +1): This unique weapon does no damage, but when a successful hit is made, the victim falls unconscious for 1d4+1 hours if it is medium sized. A large or greater sized target falls unconscious for 1d4-1 hours. A small or tiny target falls unconscious for 1d6+1 hours. A successful saving throw versus spell means there is no effect. A natural 20 on the combat roll negates the saving throw.

Staves, Rods and Wands

Druid Staff (Quarterstaff +2): This heavy oaken staff allows a druid to polymorph one more time per day. Can only be used once a week and has 1d8+2 charges. Cannot be recharged. This does not give druids who cannot polymorph that ability, only enhances those who already have it.
Holy Staff (Quarterstaff +1): This holy staff allows a cleric or druid to pray for and cast one extra spell of his highest level. So, if a cleric/druid can cast only two 5th level spells without the staff, then with the staff he can cast three 5th level spells. This item can only be used once per week. Note: The cleric must have the staff to pray for AND cast. This item does not replace spell components, even if a wooden staff is called for.
Rod of Ioun Stone Shattering: This cast iron rod has a command word engraved upon it. When the word is spoken a high pitch sound will be emitted from the rod and all ioun stones within a 15' radius will shatter (item saving throw does not apply). All others within 30' must roll a 4-6 on 1d6 to save versus shattering. Has 1d6+1 charges in it and cannot be recharged.
Wand of Piercing: This shiny metallic wand does not cast any spells. It does, however act as an effective weapon in the hands of a mage. It does 1d8 points of damage and wipes one wizard spell from the memory of an opponent (determined by DM), assuming that person has wizard spells memorized. It cannot wipe out any clerical spells. Wizard must have a proficiency in dagger to effectively wield this weapon. Radiates magic when a detect magic is cast.
Wand of Transmuting: This extremely rare and powerful wand transmutes anything (up to 5 cubic feet) into anything else (see respective transmuting spells). Has 1d6 charges, and is unrechargeable.

Armors & Magical Clothing

Bracers of Phasing (Bracers AC 4): When the command word is spoken, these magical bracers allow the wearer to pass through solid matter. The phasing process only lasts for 1d4 rounds (determined separately and every time the command word is invoked, and this number is kept secret from the player), and can only be used once a day. When phasing, he (the wearer) can only be hit by magical or +1 or better weapons. The wearer's weapons (magical or not) have no effect on anyone he attacks, however, he can cast spells or use psionics normally. This includes scrolls, wands etc. Item has 1d6+2 charges and is not rechargeable. If phasing wears off while wearer is passing through a solid object, the character is stuck. If serious enough, the character is dead, with nothing short of a wish that can bring him back.
Chain Mail of Holiness (Chain Mail +3): This shimmering coat of armor has been blessed by high priests, and those wearing it have the bonus armor class only while being attacked by undead or lawful evil creatures. This armor acts as a cursed chain mail -3 to any evil character. It is normal armor to neutral alignments.
Chain Mail of Unholiness (Chain Mail +3): This blackened coat of armor is the opposite of the aforementioned Ring Mail of Holiness. This armor acts as cursed chain mail -3 to all good characters. It is normal armor for neutral alignments.
Robe of Levitation: This mundane-looking magical piece of clothing allows the wearer to levitate as spell. This item activates at will.

Rings, Amulets, Necklaces & other Jewelry

Amulet of the Mind: This large medallion, when worn around the neck, makes the wearer immune to all psionics below a 1d8 level (predetermined before item is found). Therefore it can be from as little as first level or as high as eighth. However, in order for this device to work properly, the wearer must have an intelligence of 16 or better and must NOT be a psionic or have a wild psionic ability. If anyone that has any psionic ability were to put this on, they would suffer 2d6 points of damage, lose all PSP's and pass out for 1d4 turns.
Bracelet of Confusion: This cursed item, when donned, causes the wearer to be constantly confused and baffled. He will always get last on initiative, and is always having to have everything explained, like a four-year-old. Spell casters lose two casting levels, even if that means a loss of all spells. Can only be removed by a remove curse, wish or the like.
Earrings of Hearing: These magical pieces of jewelry allow a thief to detect noise without fail. Any other class gains the ability to detect noise like a thief of the same level as the character. One major drawback to wearing the earrings is, that any sharp, loud noise will deafen the wearer for 1d10 rounds.
Ring of Sight: This ring has a large eye on it. This item actually gives the wearer a third eye. He can use it to look around corners, etc. All rings have infravision up to 45 feet. 20% can see in the dark (as if it were lights out) or can see invisible creatures. 5% have both. This "eye" can be blinded with normal means (flash of light, etc.). The use of this item is extremely disconcerting. The wearer must practice with it for 10 hours before getting comfortable with the new sensation. Otherwise, he will have to close his two normal eyes in order to use the ring properly.
Ring of Turning: This device allows anyone who is of good alignment to turn undead as if they were a cleric of the 4 levels below the class of the person using the ring (Ex: An 8th level fighter can turn undead as a 4th level cleric). This means the character must be a minimum of 5th level to use this item. It gives no bonus to clerics or paladins. It has 1d10+3 charges in it and can be recharged only by a lawful good cleric of 12th level or higher and knows the proper incantations. Note: Holy symbol is still required to turn. The ring does not take it's place.

Potions and Oils

Holy Oil: This ordinary-looking oil is used by clerics and paladins against undead. This special oil will ignite upon contact with undead, otherwise it will NOT ignite under any circumstances. It does 1d10 points of damage in the first round. For every round after, it gains a +2 bonus to damage (1d10+2 in the 2nd, 1d10+4 in the 3rd, etc.). Can only be extinguished by Holy Water or when the creature is destroyed.
Perfume of Male Seduction: This perfume of exotic fragrance from far lands, causes women to have a charisma (effectively) of 18 towards men and must make a saving throw versus magic or be charmed by the female. Once charmed, the victim falls desperately in love with them. All rules pertaining to charms apply. Lasts 2d10 rounds. Also, Cologne of Female Seduction has the same affects only it works on the female gender.

Potions

Curse of Lycanthropy: This potion gives the drinker, the Curse of Lycanthropy (See spell in Monstrous Manual) The type is given below:

1d20 roll: 1-5 Werebear, 6-10 Wereboar. 11-15 Wererat. 16-20 Werewolf.

Lightning Body: If this potion is consumed, the drinker's body is covered with a visible, thin lightning shield. This gives him/her an Armor Class of 4 (+/- DEX bonuses). In addition to that, anyone who touches or strikes this person with a metal weapon or bare hands, receives 3d6 points of damage. Wooden weapons do normal damage but still must hit against the AC 4. The potion lasts 1d4+4 rounds.
Shadow Stealer: This potion causes the drinker's shadow to become a living entity. It behaves in much the same manner as a shadow (see Monstrous Manual) however this shadow cannot be turned. It has a 10% chance of being the same alignment as the drinker, otherwise is chaotic evil, and will fight it's former "owner" to the death using a shadow of the weapon that the drinker carries (treat this weapon as the same, but gains a +1). This shadow is the same class as the drinker, but at half the level (minimum of 1st level) but at the same number of hit points. After the shadow is defeated, the player regains his shadow.

Magical Books, Tomes, & Manuals

Manual of the Mind: This work, if read over the period of a month, and it's skills practiced, will allow any psionic to move up to the midpoint of the next higher level. Priests and wizards understand the book, but it is useless to them. If any of the warrior or rogue classes read it, they will suffer 5d4 points of damage (not to mention one hell of a headache). If the reader is not a psionic, but has a wild psionic talent, then they suffer no damage, and only gain another devotion and 1d10+5 x 100 experience points.
Tome of Valiant Stories: This storybook contains 1d6 great stories of heroic deeds. If this is read by someone, they gain a 1d4 bonus to all attack rolls for 24 hours. If someone with a 16 or 17 charisma reads it out loud to a group, everyone in the group gains a 1d2 bonus to attack rolls for 24 hours. If someone with 18 charisma reads it out loud to a group, they gain a 1d4 bonus to all attack rolls for 24 hours and get a +3 to all moral checks during that time. After a story is read, it disappears permanently.