I did the obligatory slo-mo fall when I first started using my SPDs - you know, the 'let's stop the bike and put a foot down - or not'.

Also, I didn't exactly fall, but a few months ago I got new shoes and.... let's just say that when I put the cleats on I didn't do a very good job. I went to stop and couldn't clip out at all - with either foot. Somehow I made it home without mishap; I had to hold on to a post, reach down and loosen the shoe's straps so I could get my feet out. My bike looked very strange with my shoes still hanging from the pedals.