Mark Rober used two iPad2s to create the illusion of a see-through hole in his chest.
A description of a relatively simple Halloween costume using 2 iPad2s to make it look like you have a huge hole in your torso. You’ll also need a MiFi hotspot (if you don’t have a WiFi network available where you want to use the costume). Basically you start a FaceTime chat between the iPads and then tape one to your front and one to your back. Add a little red paint and you’re good to go. It’s supposed to look like you have a gaping hole in your torso.