What’s the last thing you kept for no reason?

I found a pair of old flip-flops in the back of my closet yesterday — one with a hole in the toe, the other missing its strap. I’ve had them for years, not even sure where they came from. But I kept them. Not because they’re useful, but because they remind me of a night in Lisbon when I laughed so hard at a street musician that I forgot to be tired. What’s something you hold onto that makes zero sense?