After seeing some inspiration from the FrontPython project, I've started working on integrating a GPS option in Front Row. So far I'm developing it to launch RouteBuddy (only because I had the trial installed) and it will only with with OS X 10.5 (Leopard).
Currently I'm on release 0.2. Installer will check for RouteBuddy - it it's not installed it will not allow the installation to continue. The installer will also make sure you've got Leopard installed and it's all wrapped inside a fancy DMG now. Still using the Safari icon however...
Check it out if you'd like, I'm open to suggestions, etc... Not sure if there's a real use for anyone else but once I get my Carputer together (which I plan on using FrontRow for the front end) it should work great.
It's available here:
http://www.getpond.com/FrontGPS-0.3.dmg