RPGMemes

A magical sword that extends, but the longer you have it, the longer the incantation you have to say to get it to extend... Maybe show it some pictures of people cleaved in two, or try stabbing somewhere else to get it going.

Lembas bread but it's 1000 years past it's due date and you will get diarrhoea equivalent to its food value.

Praytell the price on yon banana blade to your left, fair merchant? I find it somewhat a-peeling

Sword with fire enchantment, fire has no regulator and cannot be turned off.

Invisibility potion that turns your digestive track and stomach contents invisible.

Arrows of Accuracy: These arrows will always hit. Starting from the target, then out from that point, the hit roll is checked against defenses.

If nobody is hit, the arrow strikes the firer.

Periapt of health: this is a small vial with a red liquid inside attached to a small chain. While wearing this, all diseases that you would otherwise contract enter the small vial instead. If the vial is broken, the closest creature will immediately contract all diseases contained within.

Deck of many things (used): the previous owners of this deck got all that they could have wished for. The remaining cards might not be the best.

Ring of mind shielding: the creator of this ring was a bit over-zealous. Along with the usual effects, this ring will censor violence, sex, and other uncouth things.

Cloak of the bat: along with the usual effects, wearing this cloak will also make you speak bat. You will only be able to produce high-pitched squeaks.

Portable hole: this portable hole is bottomless! Anything that falls down the hole is lost forever.

Flail of Flatulence: deals an additional 1d4 of embarrassment to the target while dealing 1d4 of gas damage to everything within 6 meters.

Bag of Storing, a bag of holding that doesn’t mitigate the weight of the items within.

Not quite the same, but a Paladin in a campaign I was in once bought a Shield of Missile Attraction for cheap because the shopkeep thought it was cursed.

Bead of (Uncomfortable) Nourishment: Standard effect, but must be taken nasally. Oral absorption may cause permanent magical flatus.

Leaky alchemy jug.
Whenever you use this jug roll a d100. This is how many percent of your choosen liquid are replaced by mayonnaise.

The "Sword of Instant Regret". It does 100% DMG, but only stabs the wielder.

Bag of holding with a preexisting hoarding problem

Can’t-trip - only works when you don’t want it to

Book of spells, but you have to spell out letter by letter each time you cast

Wand of Wonder What This Does

A regular wand of wonder that comes with a gambling addiction.

I have a spreadsheet full of these somewhere. The 2 that my players got that I remember them using are:

Emperors armor: +3 full plate armor with no strength or armor proficiency requirement. When you look at yourself or in a mirror you see yourself in full plate armor, but to everyone else you are naked and if anyone tells you that you are naked the armor and all your possessions cease to exist. My player made it the shopping district in the heart of the city before someone told him.

Staff of disintegrating: when activated, it disintegrates. The player that got this one saved it for a boss fight. He found it hilarious though.

And I'm stealing that idea for my game, and that one, and this one is cool too ...

Immovable Rod: Only one end of the rod is fixed in space, the other end swings freely.

Wand of wishes. It's great, but it will respond to any speaker in the vicinity

Skull of Corruption: It can do damage, but most of the time to your invaluable backup files.

Magic sword of infinite sharpness.

Sheathing the sword, or holding it by the hilt, quillons, or pommel causes it to become incredibly heavy.