From
Despair, Inc.:
It takes 46 muscles to
frown, and 17 to smile, but it doesn't take any to just sit there with a
dumb look on your face.
or, for the more
homicidal of us, from sources unknown:
It takes 46 muscles to frown, and 17 to
smile, but it only takes 4 to pull the trigger on a well-
oiled
sniper rifle