If you enjoy your robotic vacuum, why not extend it to the yard? Sharper Image has a robotic lawn mower sure to scare the crap out of your neighbors with kids — I mean save you the time of mowing your yard. I don’t know, the idea of a robot armed with sharp spinning blades scares me. Not in a Terminator sort of way but in the lawsuit-waiting-to-happen kinda way.
Besides why not just pay a person to cut your grass for you? Then you get your grass cut (probably better job too) and remove any personal liablity you might run into. AND at $500 thats probably 2 summers of cutting from the neighborhood kid.