Tractor Beams: Star Trek Fiction or NASA Reality?

Nasa is going to spend $100,000 to see if someone can come up with an actual working tractor beam. Really.

Tractor beams that can tow injured starships back to space dock or capture enemy alien vessels don't exist...Yet.  The National Aeronautic and Space Administration says that lasers can be modified to move and capture particles of space dust. So, they are willing to pay someone $100K to come up with one.

Jeremy Hsu, Senior Writer for Space.com tells us:

The investigation by a team at NASA Goddard Space Flight Center aims to examine three possible ways to control particles with laser beams. Such technology would allow robotic rovers and orbiters to collect samples from Mars' atmosphere, for instance, or give deep-space probes a longer reach for scooping up passing particles.

Paul Stysley, a laser engineer at the NASA Goddard Space Flight Center in Greenbelt, Md., says that "Though a mainstay in science fiction, and 'Star Trek' in particular, laser-based trapping isn't fanciful or beyond current technological know-how."

Hey, cell phones were inspired by the flip open, hand held communicator on Star Trek.

Why not a tractor beam?