Yeah, I've laughed at athletes that injure themselves in stupid ways. I vaguely remember a local Dallas pro hitting the injured list due to some butter knife injury (although I can't find a pointer to it just now). This article from Cracked lists a bunch, including my favorite, kicker Bill Gramatica knocking himself out for the season after jumping around like an idiot while celebrating an otherwise meaningless field goal.
But I now have to raise the bar a bit for ridicule after I sliced my finger open - on a jar of salsa.
You see, it had some of that dried salsa on the edge of the lid, and when I grabbed it, my finger caught on a chunk of pepper or something, and...
Well, I guess you had to be there.
But I'm still going to laugh at Gramatica.