Building a lawnmower bot

Stumbled on this where the author build a solar powered lawnmower robot.  Actually the controller part is solar.  Rest still is gas.  Basically its an arduino controlled robot with 2 wheelchair motors moving it along and the front wheels replaced with swivels.

http://www.d33z.com/p/robot-mower.html

http://www.instructables.com/id/Arduino-RC-Lawnmower/