Someone recently asked (possibly humorously) for information on PIC
controlled robot lawnmowers.  Well, I don't know about the PIC, but here's a
page devoted to robotic lawnmowers:

http://www.idx.com.au/~deverett/mowbot/archive.htm

It also has links to other robot lawnmower pages.  Start designing now.
Spring is only four months away.

Dave, N9LTD