Just for fun I pulled out my copies of Monsters & Treasure and Supplement I: Greyhawk. I had the idea to roll twice on the magic items tables and try to combine the results into a single magic item. Here are three magic items I cam up with:
Armour +1 + Rod of Beguiling =
Armour of Beguiling
This armour subtracts its bonus from the hit dice of the opponents of the wearer. The wearer of this armour is also able to beguile all enemies in a radius of 20' into believing that the wearer is their most trusted friend or respected mentor. Each use takes one charge and the armour has 4 to 24 charges. Beguilement lasts for 4 to 16 turns.
Ring of Contrariness + Scroll Protection from Undead =
Ring of Attracting Undead
When this ring is put on it cannot be removed without a spell to Remove Curse, and the wearer will not wish to remove the ring. It makes the wearer absolutely contrary and he will act in the opposite fashion of normal/requested. Each day the ring has a 2 in 6 chance of attracting undead. Roll on the Undead-Types table from the Wilderness Wandering Monsters table in Supplement III: Eldritch Wizardry to determine the type of undead.
Sword +1 + Drums of Deafness =
Thundering Sword +1
This sword will seem to every test to be a normal sword +1. However, each time the attacker rolls a 20 for their attack roll, the sword will cause a peal of thunder which will deafen the wielder of the sword as well as those within a 6" radius, and this deafness will last until Remove Curse spell is cast upon them.