This is a video of the Slow-Mo guys shooting metal airsoft pellets at an incredibly sharp (and expensive) SOG Knife to split the pellets and pop two side-by-side balloons simultaneously. It works surprisingly well (granted he is shooting just inches from the blade), raising the question whether it's actually that bad an idea to bring a knife to a gun fight, or if that's just an old wives' tale, like you shouldn't drink three Red Bulls before bed. "You didn't sleep at all and peed the bed twice." Shhhhhhhh -- don't tell my mom. I already changed my sheets, drank two more Red Bulls and convinced her she was wrong.
Keep going for the video.
Thanks to Daze, who agrees there are a lot easier ways to pop balloons.