Here’s a good hack that will let you install GoogleMaps Navigation on your G1 Phone. I believe the new navigation is only supported with the new Android 2.0 but with this hack, all G1 phone users should still be able to access the new GoogleMaps navigation, yey!
Make sure you have CyanogenMod 126.96.36.199, by the way.
1) Unzip zip to desktop
2) Run Part 1.bat
3) When prompted to press any key, do so; the phone will reboot
4) When your phone is running again, run Part 2.bat
5) When prompted to press any key, the installation process is done.
6) Make sure GPS is enabled
7) Open Maps and press OK
8) Press Menu
9) Press Directions
10) Enter an end point
11) Click Go
12) Just under “Show on map”, click Navigate.
13) When prompted to install the voice codec, do so.