I've always been a fan of things like watching a TV show about a TV show, observing the infinite regress while standing between two parallel mirrors, and especially looking at pictures that contain themselves.

In that spirit, I have this tradition of taking a picture of my wall and then putting it up on my wall, which I eventually did with this photo. Conceivably, I could then take another picture and put it up, then another, and another, and keep going forever, but after a while it would just get stupid.