It makes zones for the headtracking device and converts it to keystrokes. Instead of pressing a hat button you just turn your head in the direction you want to look. When you turn you turn your head back to center, so does the views.
TrackIR has really hit the simming world in a big way. Most people find it intuitive and a few don't like it. It does take some time to get used to, but I guess you, nopoop, knows all about that these days. Most of us have been playing piccolo with our fingers and have a hard time to get used to moving our heads instead.
I love the irony of it. We've learned to "move our heads" with our fingers, and now when we are able to actually move our heads we find it difficult.
I love my toys. But this TIR thingy adds a little immersion and ease into simming, once I got got used to it.
To fully understand it's potential, you have to try it out with sims that fully support TIR's "enhanced mode". Such as.... well, all but every other sim (IL2 series, MSFS, LOMAC, BoB, WB, X-Plane soon...)
checkout
http://www.trackir.com for details on the hardware.
They're launching the next generation hardware these days.
I HIGHLY recommend it for boys who like toys.