I worked at a thrift store for a few years in the 90s, and loved putting things out for sale like that.
At some point in my stint there, we sold:
A wedge of foam, like furniture padding foam, but too small to be useful. The tags read something like “Wedge of Foam! Who can use a foam wedge? You can use one! Somehow! 55 cents.” I put it on my wares cart, wheeled it out, and as I put things out, a regular customer stopped, picked up the foam. “What’s this?” “A foam wedge!” “What’s it for?” “Dunno, whatever a wedge of foam is used for, I guess.” She stuck it in her cart and bought it.
An objet d’art. Someone donated a glass Christmas-tree-shaped jar and a box of baby-doll heads. I crammed the heads into the jar, labelled the jar “Objet d’art 99 cents,” and it sold in minutes. The cashier did ask me later what idiot would have donated a jar full of doll heads.
A Sports Illustrated shoe phone; I spun off a long strip of tags and wrote in tiny handwriting a full transcript of the long “Hey! It’s a shoe and a phone!” commercial that used to run in the 80s, taped one end of the tag strip to the phone, and put it out for sale. My manager began loudly chastising me for goofing around and wasting tags-- in the middle of the tirade, a customer found the phone, began laughing at the tags, and decided to buy the phone simply because they liked the tags. Which ended the tirade.
A baggie of gravel. Out of boredom, stuck a handful of gravel into a baggie, labelled it helpfully as “a baggie of gravel,” snuck it into the jewelry case, where no one noticed it for days until a customer asked a manager about purchasing it. They bought it (something paltry like 11 cents), but I did get in trouble for that one.