Laser Propulsion

It is likely that it "could" be done. But not currently practical. Here is an address for an interesting article on a laser powered aircraft. http://diydrones.com/profiles/blogs/laser-powered-quadrotor-sets

I wonder if that's the same Jordin Kare who composes "filk" lyrics for science fiction and fantasy (SF&F) conventions.

Yes, but then so could a torch or a jet of urine.
The thrust would be very small, although of course it could be increased by chucking it out the back.
Del

There are science toys that look like a light bulb with a black and white rotating device suspended in them. Shine a laser on the black part and see if it speeds up, that will answer your question. For every action there is a reaction, but the laser has very little mass, so the push is slight.

If you can add enough power, you may have something. I would expect at high thrust, the laser will be consuming something. It's gotta have something to spit out, at that point it is called ion drive, I believe.

"I'm giving it all I've got, Captain Kirk, but it's just not enough" (Scotty).