There was the flowback back in ~2006 who didn't want to wait for the ramp freq to clear him to taxi off of G19, so instead he just spun a hard right off the gate, and wedged his RJ onto a concrete barrier that he didn't notice. A month or so later some genius spray-painted "flushback mountain" onto the barrier. It remained there for over a year before it was painted over.

Overall though the flowbacks were very good to fly with.