It's a desk that's attached to an elliptical machine. The machine is "designed to be pedaled at slower cadences that won't break one's concentration (or cause one to break a sweat." I don't know why anyone would need these, I just run in place while I'm seated at my desk. Burns more calories, and the impact of the foot hitting the floor builds more muscle.
This is the brainchild of botanic artist Makoto Azuma and furniture designer Herman Miller. My question is, when will they make a version for a La-Z-Boy or other oversized recliner? More people watch sports in those chairs than in office chairs, anyway.