New Scientist has an article about small robotic fliers. The Entomopter is being developed by Robert Michelson (and his design team at Georgia Tech) and is an aero-moth-bot that uses a reciprocating chemical muscle to flap it's wings up to 30 times a second. It looks like they received part of their funding under DARPA so their web page isn't updated anymore, but it's still worth checking out. Makes you wonder how far the design has progressed since then. Wouldn't it be cool if they'd sell these things as toys. :-)

Here's a Entomopter wing flapping video. And, here's a flight test video.

There's some other articles here and here and here. It also seems Robert is heavily involved in aerial robotics competitions in Atlanta.