Any insights would be great.
Peas and love.

I haven’t been keeping up too thoroughly with whether there is any head mounted display out there with a Mac compatible SDK for 3DOF head tracking built in. The emagin goggles I’ve been working with (~$1500) for a while only had a PC compatible accelerometer in it, but it was so noisy I haven’t even bothered to check again if it is finally Mac compatible.

Vuzix http://www.vuzix.com/home/ HMDs are getting less expensive (under $1000), and I’d consider looking into them as an option, but the quality of the head tracking is what might really cost you. Motion Node apparently makes the cheapest USB 3DOF tracker, but I think it’s still $1000. Intersense makes a relatively small bluetooth InertiaCube and the quality is quite excellent (and I’ve had some success getting their USB and Ethernet devices working in Max/MSP externals).

I’ve seen a few DIY projects with things like iPhones, Wiimotes, etc mounted to the users head. You really want to make sure you get something with a gyroscope in it (not just an accelerometer). But if you don’t mind strapping something like this to your head…

My only advice in purchasing a display (since there’s such a range) is to double check what connectors and Max resolution you are getting. This is less of a concern in the $1000 and up range, but the cheap ones you want to make sure have a resolution your computer supports and that you haven’t inadvertently purchased something that connects with component or RCA cables or something that only connects to your iPod (adapter sold separately).