Remember the automatic doors from the Star Trek TV shows? The one you always wanted in your house someday? Now you can build one yourself via this DIY pneumatically powered door tutorial. At first glance, the door appears to be normal but as the video above shows, it’s definitely not.
An air vent was added above the door to let the pneumatic sound through and complete the Star Trek effect. Of course, instead of a key switch, it would be better if it had a motion sensor. It is controlled by a PIC microcontroller and the air-power comes from a small air compressor that drives the pneumatic pistons. Check out the complete build instructions.