7 Minutes in Purgatory is a comedy routine unlike any other. The stand up comedian is placed in a sound proof room, with noise canceling headphones, and no windows or pictures of their audience. A light on the inside flashes for when they start and when they stop.
The audience has a video of what the comedian is doing and saying live. However, the comedian has no idea how the audience is reacting. I can't image how hard this must be!