Only a few pair of old egg beater cleats that I have laying around the workshop.
However, somethings are probably useless and a hindrance. Take for example old cleats. If I've taken them off a pair of shoes, it probably means they suck ass at keeping me held into the pedals. I don't know why I've kept them. Maybe in the back of my head I had plans to make a life like mosaic of myself with all the spare parts.
My last mountain bike ride, when I crashed, I was unclipping horribly - not that that was the reason for the crash. But it was time to replace the cleats. Finally got around to it yesterday. BUT, I did not have a new set to replace them with. So I go digging in the tickle trunk to find a suitable pair.
Pffft . . . good luck finding a pair that are any better. How the hell do you tell?
Crank Brother Egg Beater pedals - in my experience people either love them or hate them - I heart them. However, my one beef with egg beaters is that the cleats wear out way too quickly. Soft brass is no match for steel or ti spindles or hard rock. I usually end up replacing my cleats two or three times a season.