Leave it to a rocket scientist to come up with the greatest Halloween costume - and all you have to do is download an app. Mark Rober is a NASA engineer who created a costume last year using two iPads to create a hole in his stomach. He put a video for the costume on YouTube that was seen by more than 3 million people. Almost all of the people who saw the costume loved it, but complained about having to spend more than a thousand dollars to make it work. By the way, Rober designed a lot of the components for the Curiosity Rover that is now giving us some pretty cool images from Mars.

After reading the cost complaints, Rober created an affordable costume called Digital Dudz, which is a free app for iPhone and Android users that is made up of of some very cool interactive videos featuring moving eye-balls, beating hearts and much more.

You basically download the video you want from the app and attach your iPhone or iPad to the inside of your shirt. Make sure you cut a hole in the shirt first, then line up the phone with the hole and you have one of the greatest costumes anyone has ever seen. The practical joke potential with this is unlimited. See how it works below. You will SO want to do this!