I recently upgraded to a "smart" cell phone with Hot Spot tethering so I can connect my laptop to the internet from anywhere.
You can use Michael Obourne's APM Planner instead. He has offline maps.
So i will test the APM planner, but, whats happens if we use another maps source without internet conextion. It is possible?
A few years ago with the earlier version of Google Earth there were some third party free programs where while Internet is on, you can set an area on the map (where you plan to travel) and this simple program would systematically "visit" those areas in a grid-type fashion and store the kml(?) or some other files on your hard drive. You can map hundreds of miles, of course you would need a large cache set first and would take couple of hours. When it's done and you can go offline and point Google Earth towards that "recorded" cache and when you travel there it will pull up the actual location into Google Earth.
You had to set altitude, etc. In smaller areas, a few square miles of known territory you should be able to set several layers of altitudes.
Java is way beyond my knowledge, but found this: http://code.google.com/p/gmapoffline/
Not sure how legal it is, as I read Google places restrictions on some use of its products.
Do you find the time to do it?
I`m very interested in this feature.