aha when i was like 11 i was actually alright at that! i could like do 360s of tables and like ride along thin things and jumps gaps and stuff. but i agree it isnt good on the testicles, dont think i could do it now, added to the fact that doing it seriously is abit gay.
my younger brother was like that. He was actually incredibly good at it and still is, but just doesn't do it too much anymore.
My town has the largest children's circus in New England - Gym Dandies - that almost everyone in my town was in at at least one point or another. I was in it for maybe 2 months. Anyways, everyone learns to ride a unicycle and some kids get really good at it and buy their own better unicycles - my brother being one of the few.