While some here may think the use of a multitool as a weapon is a humorous idea, I've given it a lot of thought.
Inasmuchas I carry my Leatherman PST most all of the time, I've actually given a lot of thought to this question and to just how one might use a PST as a weapon.
Deploying the knife blade is quite unlikely. For this reason, the PST fits the original poster's needs perfectly. It would be difficult for anyone to reasonably claim that the PST is an edged weapon. This also means that you really can't plan on using it as an edged weapon.
However, it's fairly heavy and yet easily held in your fist, so it's a great punch weight.
It's made of stainless steel and has lots of "sharp" edges (not in the sense that we usually mean sharp edge around here, but rather edges that don't have nice, soft curves. As an impact weapon, it's be dandy.
If you can get the pliers unfolded with one hand quickly, they'd be a great impact and slashing weapon. If you can get them open quickly with one hand, that is. I can.
http://www.4cs.net/~gollnick/images/VIDEO000.avi
Of course, there's also the possibility of pinching with the pliers, but since they don't have a spring to open them, opening them requires relaxing your grip and it's possible to drop the weapon... I mean tool.
Some of the best targets to go after are the kidneys, the biceps, under the arm pits, the Adam's Apple (just above the boney V where your neck meets your chest), and, of course the face and especially the eyes.
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Chuck
Balisongs -- because it don't mean a thing if it ain't got that swing!
http://www.4cs.net/~gollnick