I did something similar. I was using a Kryptonite-style lock that was beginning to have some troubles at the keyhole. Well, I locked my bike up at a store and when I came out the key no longer worked. It would go in and just spin around without unlocking the darned thing. It was rather stupid to keep using a lock that was giving me plenty of warning that failure was imminent. Lucky for me, a person who always wanted to try busting one of those locks open with a car jack came by. We weren't very good at it, but in about ten minutes we had the bike free. Just like the videos, many people watched us "steal" my bike, but no one bothered to do anything about it.