Having been a youth in the early 80's, I have always been a fan of the toys The Transformers. When the new round of movies came out a few years ago, I thought it would be fun to build a fully transformable version of the quintessential Autobot - Optimus Prime.
I started by buying the toy ($80???), taking it apart, and modeling each part using the engineering design package Pro/Engineer. I then built each part out of maple. Every part was machined by hand. He is finished using dyes and spray lacquer.
He fully transforms from a Mack-style truck into the robot. In robot mode, he is about three feet tall. He sits on a maple base that rotates on a Lazy-Susan, for easy viewing. Even the Autobots logo built into the base is made from maple. I would estimate that I have between 500-1000 hours into this.