Last time I went to MOMA, there was a huge composition that looked like an all-black canvas. Didn't look out of place. But when you get closer, find that it's covered in a thick layer of dead flies. It was a hoot. Take or leave the composition itself; the biggest fun was in watching other patrons' reaction to the piece.

When I buy art, it's usually from folks who live on the street, not from galleries.

edit: found it https://www.damienhirst.com/texts1/series/fly