You know there are people all over who deserve a good ass whoopin.
It's just not socially acceptable to make people bleed (under most circumstances - unless you're a surgeon or phlebotomist or hockey player). Plus, you don't always have your nanchakus with you.
So today, embrace your urge to show someone that there's someone who doesn't need messin' with (YOU, that's who), and they'd better step back. Get into your most fearsome crouch, hands splayed in appropriately threatening manner, and say 'WAAAAAAAAAAAH!'
Then turn around and walk away, saying, "Don't MAKE me go all Kung Fu on yo' ass."
Disclaimer: if you get your ass kicked by someone who actually knows Kung Fu, sorry. You're on your own. Also, this move not recommended for dealing with Officers of the Law.