[lomendil]

Eye tracker hardware is tricky and therefore usually expensive, but on the software side there are good tools. I've used VisionEgg[0] with an Eyelink II system and found it quite easy to deal with.

[0] http://www.visionegg.org/

[dchichkov]

Not that expensive. For a couple of hundred dollars you can build very nice 60-90fps IR eye tracking system. You'll need IR camera, IR tele lens (very important), couple of IR sources and open source tracking software. See http://www.gazegroup.org/develop/

There is also alternative approach. If you are just recording and don't need interactivity - all you need, is a regular camera with zoom and a small tripod. You can record on an SD card and synchronize the stream stream time in post-processing. Just flash the monitor screen couple of times at the start and the end of the recording, and play tracking alignment sequence.

Here's an attempt to do just that: http://www.youtube.com/watch?v=zJqKRL9D2qY

[tejaswiy]

I somehow assumed this was done with a webcam eyetracking software .. my bad.