Full Auto Slingshot Minigun!
Full Vid: http://www.youtube.com/watch?v=-q5URmC5BMk&t=180
You can watch the whole thing from the start - it shows a bunch of other slingshot pistols he's made, or go straight to the saw-slinger:
the fact that he even got the blade to shoot straight is amazing to me
before you take possesion,you'll need a background check, and then it will have to be registered. Now that makes me feel a lot safer.
Only a German could create something like that :P