Careful, you'll end up on a "Wanted" poster, courtesy of the Consumer Products Safety Commission! Seriously, I have a coffee can full of those things, too (my sisters just loved 'em when they were kids). I took a liking to them, too - they are just about the meanest thing you can launch with a Wrist Rocket slingshot. Like a miniature Ninja star. I mention these things purely for educational purposes, of course... ;-)
This might also be a good opportunity to try out the ol' paintball gun - with *frozen* paintballs. Non-lethal, and biodegradeable!