http://www.cracked.com/article_19605_the-5-most-terrifying-sci-fi-upgrades-to-deadly-weapons.html
Sprave is a slingshot enthusiast who specializes in building slingshot guns that shoot things in ways they aren't meant to be shot, which according to our calculations puts him approximately 1/3 of a minor tragedy away from taking up supervillainy (we're assuming villainy, because there's no way a hero would design a slingshot that can launch machetes in an arc of bladey horror that is heading for your face right now).
Neat!

