We have these lovely curbs in suburbia that go from street down to driveway. (Serve as rain-flow channels) Well, first time out on the fixie, I head over the curb, not realizing that the front wheel is below the rear for a second and the low pedal catches the driveway. The bike starts getting all wobbly on me and down I go. I wasn't hurt, although I was pretty glad I was wearing gloves (another hole).