Seen in traffic just now:
Fascinated, when I returned to my office, I looked up “unicycle football”. And sure enough, Wikipedia says:
The Unicycle Football League is a Texas-based league for the sport of unicycle football. Unicycle football is similar to American football except that it is played on unicycles.
No surprise there, I guess: it’s exactly what it sounds like. This proves there really is a sport or hobby for everyone.