You ever buy a used VMU or memory card and look through the files on it to see what the previous owner played, or if he's got any stuff like custom maps or unlocked content lying on there?
I find it pretty interesting, though I definitely wouldn't go out and purchase a random card simply to see what's on it. I had to purchase a VMU recently, and checked out what was already on it. Found a replay file for Capcom vs SNK and I feel compelled to watch it.