Old Spice Muscle Music from Terry Crews on Vimeo.
Via Mashable:
The coolest part is after the ad ends. A recordable player pops up and users can create their own sounds by pressing different keys on the keyboard. The keys control various sounds from Terry and different beats. Trust us, you’ll get sucked into this one, quickly. Users can record their creations, upload them to Vimeo and then share them across the web.