The LEGO Paper Airplane Folder
This machine makes (and launches) paper airplanes. The video is only 40 seconds long (it's running at 3x the machine's actual speed), but wow:
The above is actually the second version of the machine. Here's a much longer clip showing the first version, in realtime, allowing you to see the guts a lot better:
And finally, here's the original video in realtime. It's a little less exciting, though the launch at the end is pretty awesome!