I'm sure it doesn't feel good to bang your head on a rim or backboard but it's a problem many ballers would love to experience atleast once just for storytelling purposes.
6'6 DeMatha Catholic High School sophomore D.J. Harvey now has one of these stories after he almost gave himself a concussion after blocking a shot and smacking his head on the backboard.
Now he knows how Michael Jordan felt when he did the same thing at UNC.
A couple of years ago during a Sprite Showdown contest, I got to witness pro dunker/streetball player Roscoe Johnson hit his head on the rim after throwing down a windmill. I guess it sucks to have so much hops....actually, I'm sure it's worth an occasional headache.
Source: The Big Lead