Recon Instruments' $430 CAD "Transcend" goggles include a GPS receiver and a heads-up display. According to the website, it is "completely non-obtrusive for front and peripheral vision, making this real-time head mounted display the ultimate solution for use in fast-paced environments."
On the HUD are speed and distance traveled, a virtual odometer, temperature and location. You can also hook it up to a computer to download GPS-tracked records of your visits to Stambul and Freeside. They're taking pre-orders at the official site, but my feeling is this is something that needs to be experienced first-hand before even thinking of plunking cash down.
Product Page [Recon Instruments]