Black and Decker CMM1000 19" Cordless Mulching/Rear Bag Lawn Mower. You
don't need to use the rear bag. About $430 at Home Depot, WalMart, etc.
Been using it for three years for about 45 minutes of mowing once or
twice a week during "the season."

Only complaint is that with tall, thick grass or wet grass it can bog
down and stall. OF course, even a gas mower can do that. But this one
is more prone to do it. Other than that, a breeze. My kids mostly
operate it. It is a bit heavy, but who has to lift it much?

If you want truly automatic:
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Auto Mower
The Husqvarna Auto Mower is a battery-powered mower that works
independently. Mowing in a random pattern for consistent coverage, your
lawn is always freshly manicured. The Auto Mower takes itself to the
charging station and then returns to the lawn automatically, fully
charged. The mower's working area is defined by a boundary loop along
the edges of the lawn. The mowing action is continuous and the cuttings
are redistributed to the ground as fertilizer.
++++++++++
Husqvarna is a longtime leader in chainsaws. About 10 years ago they
introduced these auto mowers, they've been through a few generations of
them and I think they have them down pretty well now. Even have a solar
charged model.

You can see their website at: http://www.usa.husqvarna.com/

Just go to the lawn and garden section and then to the "auto mowers"

Here's an old reprint from Dec. 2000 issues of popular mechanics:

http://www.friendlyrobotics.com/abou...lawnmower.html