Ok. I admit it. I like the elliptical trainer. It’s easy, efficient, and doesn’t hurt nearly as much as running. But last night, ovalizing myself toward nowhere, with nothing on TV and too much mopey indie rock on my iPod, I finally got bored. I started missing group sports. Unfortunately, my only real experiences have been with ballet (I was the short, roundish girl in a room full of spindly 6-year-olds) and karate at a smelly South Philly dojo. By then I was 25, not as round and scared to death of the killing machines in my class.

So I’m still not entirely sold on martial arts, but this looks mesmerizing … and fun. And you can do it with a friend or an enemy.