I've got a work bench full of sockets, wrenches, screwdrivers, utility knives, etc. that I've found while riding. However, I think that the most surprising thing I found was my bicycle that had been stolen three months previously. It was being ridden by a young man and after a brief discussion we decided that it needed to go home with me. I didn't ask if he had found anything on his ride but he would be a good candidate for a thread about things lost on a ride.