Landed on my knee off a bike also. Except I landed on asphalt 'cos I was trying to be badass and stand on my bike while it was moving. But I think a rock might hurt more. :o

Made a kickass rock swing which cracked the top of my skull.

Played "Let's see if you can hit me with flying cacti parts." I lost. : [

Did a sweet ass flip off a trampoline and somehow busted my front tooth (in half) on one of the bars.

Rock hit by a golf club landed right above my temple thingy.

And many other sweet things. : D