So last summer my friend and I got REALLY into this dance technique called Jumpstyle. It originated in England but was dominated by the majority of Europe. I'm trying to find a place to start doing it again. I lost a lot of weight when I was doing it a year ago. i think it makes for a great cardio routine. Here's a demo vid:
http://www.youtube.com/watch?v=SOe38akbsmo
