Mike Ball is a practitioner of BEAM robotics. As the site describes them:

BEAM is an acronym standing for Biology, Electronics, Aesthetics, Mechanics:

Biology -- It's tough to beat 4 billion years of evolution; the world around us is a wonderful source of inspiration and education. Bear in mind, of course, that unlike Mother Nature, you also have the advantage of gears, motors, bearings, and good glues!

Electronics -- It kind of goes without saying, but this is what we'll use to drive our creations. BEAM robotics, though, strives for rich behaviors from simple circuits. Here's the key: simple and understandable circuits, surprisingly complex in behavior.

Aesthetics -- This just means your creations should look good. I'm an engineer, but even I appreciate a good-looking design. Besides, if a design looks "clean," it's more likely to work (and easier to test / debug) than a design that's tangled and unruly.

Mechanics -- This is the less-than-obvious secret of many successful BEAMbots -- with a clever mechanical design, you can reduce the complexity of the rest of your robot (reducing the number of motors and sensors, for example).

Quite a few of his little mechanical devils are on display here. Check the November 2002, listings.