I just got DayZ on friday and loved it despite dying constantly. I was shown that while running I could press * and look behind me to see what was chasing, I went routing around the controls to see if there was a better way to do it and noticed a few keys reserved for tracking. I can't afford a TrackIR so I googled how to make my own and found Freetrack a day later and voilà! http://imgur.com/xoyYQ

Works pretty crappily if there is any sunshine, pretty great with the blinds down and amazingly in the dark! I used the lens from some Real D 3D glasses from the cinema to help filter light during the day and it works fairly well, will be hopefully modding an old 360 camera tomorrow for infrared =)

Now I can look over my shoulder without pressing any buttons :P

Here is a video of the Track IR in play, not made by me, but mine gives a similar functionality: http://www.youtube.com/watch?v=GHMC8jUS7aM

That is awesome

This is great! Really want to make my own head tracking system now.

Reading the site, I came upon this: http://naturalpointofview.blogspot.com/p/trackir-anticompetition.html

The TrackIR guys seem like horrible people for trying to prevent this sort of open source development of head tracking systems...