Everyone and their mother does P90 or the more extreme version, P90x. But I recommend the even more extreme "Insanity", you know, if you hate yourself. They're pretty good workouts.
Still, in the workout world, weird diets and exercises pop up all the time. Any kind of liquid diet, for example, or the Shake Weight. However, none of those strange workouts are as creepy as this ab-centric one. Watching these people laugh their way through lunges is disturbing. I understand the concept; laughing forces the abdomen to contract and during exercise it will make the muscles work harder for more gain. That doesn't stop it from being ridiculously creepy. However, there is a pay-off; Watch the woman's face at the end of the video. The unpleasant wait is somewhat worth it.