UPDATE: The CAB or EXE file is still not available on the TechEd site; It's accessible from the following link but it may be an oudated version. I don't know as I haven't seen the current one:
http://studierstube.icg.tu-graz.ac.at/handheld_ar/medc.php
If you're going to TechEd 2007 in Orlando, check out Signpost. It's uses a image recongition program and your phone (Windows Mobile) to locate you on the floor and guide you through your sessions. Very cool
https://www1.msteched.com/signpost/
Link to YouTube - Signpost 2007
http://bmarb.spaces.live.com/Blog/cns!91B9647DD75C91F9!446.entry