The TrackIR 4:PRO includes full 6DOF capability using NaturalPoint's exclusive Vector Technology. This literally means that users can move their head any direction and have their game view move correspondingly – instantly providing improved situational awareness in flight and racing sim cockpits, or on the field of battle. Vector allows you to expand your view control to a full range of motion, in all six degrees of freedom (6DOF) including X, Y and Z axis, plus yaw, pitch and roll. No matter how or which direction you move your head, Vector instantly captures it with extreme precision and accuracy.

Link

Be handy I guess for cockpit view in a plane in BF2 (supported) during a dogfight
Bit hexy tho at $USD 150
Pity you couldn't try one of these things out in a store first eh?

Sounds useful except my monitor doesn't move around with my head?

yes it does u big monitorhead

Sounds useful except my monitor doesn't move around with my head?

From what I can see you control mouse movement via a cap controller by incremental changes on your heads position

http://www.edimensional.com/images/vectorintro.jpg

This kind of stuff in theory has been good, the problem is that, as trog rightly pointed out, as your head moves the placement of the image remains the same, even though the perspective of the image might change. This in itself makes it useless.

CART Precision Racing tried years ago to work with a feature whereby the drivers eyesight moves as you turn corners, problem is you just don't behave like that. Except when you're trying to sight cars alongside you, your head rolls, not yaws.

Flightsims have the same thing, your yaw head motion is likely to be quick, slower than the system can react.

vr goggles where r u