Today's chuckle

In a recent edition of Rolling Stone, Robin Williams says that this is his most favorite joke. I think it's funny as hell. You probably won't like it.

Guy's having sex with his wife. All of a sudden he looks over, and there in the doorway is his son, about eight years old. Kid looks horrified, and the kid runs away. The guy says to his wife, "Well, I'd better talk to Timmy."

He puts on his clothes and goes to Timmy's room. He opens the door, and there's Timmy nailing Grandma. The father goes "Oh, my God!" And the kid goes, "Not so funny when it's your mom, is it?"