The PS3 Eye Web camera was built to be used only on the Playstation 3 System, but thanks to AlexP from the NUI Group forums, it is now able to be used on computer systems.
Benifits
Very inexpensive. Retails for $40 USD
Capable of 320x240 resolution at 120fps (125fps experimental), and 640x480 resolution at 60fps (75fps experimental).
Easily able to take the camera apart and remove/insert neccessary filters
Uses the USB port, which is more common than the Firewire port used on more expensive camera
I have made a video showing all the steps needed to remove the IR blocking filter from the camera's lens. If you would like to simply buy a modified PS3 camera from me check out my store here.