I was messing around with my Navi today and found out that you can read your exact elevation, longitude and latitude coordinates. While in the Navi mode just push the circle with the red arrow showing your location on the nav screen and an Info screen will display showing these readings. Check it out!!!!

 

Or you can say 'Display current location' and it shows you the same information while telling you the addy.

 

You can also go through the hidden menus (map+menu+cancel) get to the GPS menu, hold down the menu button and see it all change in real-time.

 

Didn't know that. Will have to try next time.
Thanks.