Secret bookcase Entrance
this project, torn down after the Homecoming Dance at my High School, was to build a Wayne Manor style secret entrance to the exclusive Senior Lounge. Instead of a real bookcase, due to construction and time concerns being a low priority for the school, we used a flush wall door and covered the area in bookcase wall paper. To open the Door, a bust of William Shakespeare is flipped up and a hidden switch in the bust activates the motor attached to the door. the door opens, the switched is turned off, and the person may enter. We planned to make our own bust, as I do have the materials and skills, but someone found a place that sells them so they bought one as a convenience.
I use a motor with some basic gears going to a rubber wheel, entire motor assembly was purchased at a surplus store for $7 - it was driven by a 12VDC Wall Wart that was controlled by the bust of Shakespeare. I could have put a switch on the inside to reverse the polarity to the motor, so that the door would automatically close, but since this was installed the day of the dance we did not have time, and I had other areas to work on.