Showroom
Here is my interpretation of the FCG using gears instead of a crank arm.
http://api.ning.com/files/mFRFQzEllW3MaNK7A9j3Cvz2oZajSgHh0AJKXqZmpZLSeTu0oo-NWDOi5a3xk7Yr*yz8FqlYhpoZfagmIUZUBc70bISdjiLv/Step14TheGhostunderUV.jpg?width=640&height=480
You can read my how-to here...