The Revolver: locksport practice gadget that makes four locks out a single core
by Cory Doctorow from on (#3895D)
https://www.youtube.com/watch?v=TawqlKebBOs
Sparrows Lockpicks (previously) has just released an extremely clever practice lock called "The Revolver" that makes four locks out of a single core: "Pinning configuration starts with Standard pins at 12 o'clock (Marked with a small arrow) and then moves clockwise to Spool, Serrated and finally Mushroom pins. The end result is a lock that gets progressively harder to pick open." (more")