Shockwave by IndoRow is a new group exercise class I tried in August. I loved it. I felt the class was the perfect blend of intensity, overall conditioning and most of all fun. This workout is getting lots of media attention:
http://healthland.time.com/2012/09/24/we-tried-this-shockwave-rowing-workout/
Try the workout if you get a chance. This class is a great embodiment of a general trend in fitness where workouts deliver a lot of benefits in a minimal amount of time.