A hat that, when left alone with another hat, will mate and produce hybrid offspring
Negative gold pieces
A map that is the territory
Armour that becomes more effective the uglier the wearer
A living pocket-watch that never needs winding, but if you don’t feed it, it dies; it’s an obligate carnivore
Goggles that put censor bars over monsters of the Aberration type
An instructional tome in the secret language of ducks
A dagger that glows in the presence of one particular goblin
Angry shoes
A magnifying glass that interrogates unexamined assumptions
A quill and inkwell set that lets you write with perfect fluency, but only in languages you don’t understand
Clothing whose colour and pattern are literally impossible to describe
A magic potion that renders the imbiber both incredibly persuasive and extremely gullible
An actual key to your heart
Kind of in the same spirit, there’s a crappy magical item generator right here: https://rexiconjesse.github.io Ive been. Extremely tempted to inflict some of these things on my PCs.