A paracord slungshot. Kinda cool, and probably hurts like heck when you get beaned.cry Just don't take it out in public. New Hampshire, and a lot of other states, don't like those.

http://law.justia.com/newhampshire/codes/2006/nhtoc-xii/159-16.html

EDIT: How did you get the ball bearing to stay put inside the monkeysfist? I tried making one using a large marble, and I couldn't get it to stay put when I was taking up the slack.
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Hope for the best and prepare for the worst.

The object in life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane