Careful what you joke about on April Fool's Day.

Google was one of many tech companies Friday trying to get a chuckle and maybe fool a few Gmail users with a “new product” called Gmail Motion, that would allow users to “control Gmail with your body!”

Google even produced a mock video explaining how it would work. Users could move around in front of their computers, shaking their fists and licking their hand to simulate placing a stamp on a letter, and tapping their knees to reply to emails.

But the NYT reports that hackers at the University of Southern California Institute for Creative Technologies decided to take the joke on step further and make it happen. They took a Microsoft Kinect sensor and some software they already had and launched a real version of Gmail Motion.