We have an external that works with trackers from Intersense. Specifically it's been designed for the IS 900 VETracker. If anyone is interested to get an interia-cube running with the same external, I can provide the code, I'm working on a consolidated project page at the moment... will be up soon.
Can be downloaded as part of our helper objects for Cosm used for augmented reality environments.
Once the external is installed you'll need to download and install the dylib from here to /usr/lib/ since the company ask it not be distributed with the external.