HELP Ignition Key Wont Turn

:banghead: I have a 1987 635 and I went to start it and the key wont turn. The lock cylinder was moving freely the night before, and 12 hours later the ignition wont turn. I tried using my spare keys with no luck. Does any one have ant ideas before I take a slide hammer to the lock. Also if I do rip out the lock cylinder will I be able to start and drive my car or is there some kind of BMW antitheft device in the lock?
Any advice would be great. It is 7:30 Pm Saturday and I will be working on getting my lock fixed tomorrow. :2cents: So any thoughts between now and noon could help. :2cents:
Does anyone know the correct way to rip out the lock cylinder anyway?!:banghead: