The concept of electric skateboards has always piqued my interest; they are the closest thing we have to Marty's McFly's hoverboard. There is no lack of working production models
and cool DIY projects: http://www.instructables.com/id/DIY-Electric-Skateboard/ http://www.instructables.com/id/Propeller-Powered-Skateboard-1/ http://www.instructables.com/id/Easy-build-self-balancing-skateboardrobotsegway-/
I wanted to take a crack at it myself, but the components seemed more expensive than the a fully functional board (≈500$). Once I saw the "Turfboard Deville" being liquidated on Ebay, I knew I had to make it happen. Skip to the last step to see the disappointing results (so far...maybe) otherwise check out what I've attempted to do in the steps. Feel free to comment if you have an elegant solutions to my design issues.