P90X is a home fitness program developed by Tony Horton & Beachbody. You can do P90X at home with simple exercise equipment, since it is just a big set of DVDs with different workout sessions. Over the years, it became widely popular – sales are rumored to be close to a billion dollars a year. On the surface, P90X may look like many other low-tech video exercise programs. However, on a deeper level, P90X shows a brilliant social design; a design so successful that many Silicon Valley startups would envy it even today, a full decade after P90X launch. This essay will explain how P90X ingeniously hacks human behavior to help people get healthier, seemingly against their own will.