I bought a piece of 1.5 inch stiff foam to try to fix a sag in a bed. It didn’t work but having that thick piece of solid foam around has been a life saver.
Need something flat to put a laptop on? Throw it on the foam. Going to be doing something that requires you to be on your knees for a while? Get the foam!
It went from stupid purchase to something I’d gladly replace if it broke.
A mini keg of a Christmas beer. At the store after drinking a bit, thinking “Oh it’s a little cheaper per ounce, lol”. My wife rolled her eyes, but she lets me do stupid things. Next day I was thinking “Well that was stupid.” But it was a few days before Thanksgiving, and we opened it then, and it turned out to be a lot of fun. Draft beer, at home! Fiddling with the stupid pour thing. It was just fun to have something different.