If you really want a beastling to take care of your mowing you shoud try a goat Helen. One of those miniature thingies that don't grow more'n a foot high. They are apparently quite docile and love to chomp on overgrown grass.

The only thing you might have to worry about is that old "what goes in must come out" scenario. Personally, I'd stick to an electric mower.

Oh, and um, what is it about sheep and Welshmen??? I've never heard anything.