One rope + a little yankee ingenuity, and you've got yourself THE lazy man's lawn mower.
Korey99's self-propelled mower runs on autopilot:
"It's cutting most of the back yard (a large circle) by wrapping a rope around a couple of stakes.
The video is played at 4x speed. Yes, we have a lot of weeds, and yes, I need to grease the wheels.
Also, this is dangerous, so kludge at your own risk."