Robert Smith built this Remote Control Solar Lawn Mower to let him cut his grass without breaking a sweat. Check out a few of the many videos below that he created going over the entire build process. He used Google Sketchup to make a 3D model of the system before it was built, this would allow you to make your own lawnmower if you choose. Just like with other robots electric wheelchair motors have been selected to drive this mower. The videos are great since it looks like Robert must have a video production background.
Thanks for sending this in Robert!