I usually unlock the bottom lock and use deadbolt only, because that one I do have to manually lock (and it's more difficult to jimmy). I don't know why I didn't yesterday. I also don't know how I managed to not even realize I didn't have my keys until someone pretty much pointed it out to me.

Of course, I had a particularly dingy day yesterday - I left the office with the keys dangling in the lock as I raced to go do something else. Er, yeah. Whoops.