While cutting the grass this afternoon, my mower overheated due to the long / damp grass. I decided to call it a day before realising that I'd "accidentally" mown a neat little circuit in the back garden:
http://twitpic.com/5h829d
That doesn't entirely do it justice but I can confirm that it does pretty well as a grass circuit. Just don't tell the wife that the mower is now running fine again.