When the folds (Wrinkles) in a scrotum resembles that of a smiling face. Eyes and Mouth are required, nose is preferred, but not required. THE SACK MUST BE HAPPY!!! Must be declared by a spectator, not the one whom the sack belongs to!
If the "FACE" is hairy, 'Ball Bunyan That Smiles Back' may be decalred!
Donny: Dude, George, I think I got The Sack That Smiles Back, but I'm not sure... Help me out
George: O, definitely dude!! I can feel the happy vibes going on around your nutsack. That even may be a 'Ball Bunyan That Smiles Back!'
Donny: GET THE CAMERA MAN!!