I've been following Jon Udell's blog for the thread re data control and privacy, and found myself bemused by his habit of watching the landscape scroll past from the airplane window seat. A soul mate! I've been taking the window seat for some 35 years now for the same reason, and still can't get enough of it. It's a show to beat whatever rubbish is on the seatback LCD panel. Snake River canyon! Center pivots! Greenland fjords! Tracing defunct railroads across the old Northwest! What's not to like? I've picked vacation spots just because I had to get my feet onto that terrain down there.
Jon's got some ideas for a realtime synch between Google Earth and his airborne position. GE is a bit bandwidth consuming, let's say, for in flight use. My recent wanderings have featured another solution. Since I've gotten bitten by the geocaching bug (I can quit any time...) I've had a hand-held GPSr along on trips, and they turn out to work quite well airborne. Yes, you're in a metal tube, but the improved LOS to the satellites seems to at least offset that problem. (I use Magellans, because they'll hold lock in redwood forests, but the latest Garmins with the SiRF chipset are as good or better.)
Turn on backtrack and set map mode for a large span, then work on calibrating your 'head declination' against lateral distance from 35,000 feet. I've never bothered to download the track into a mapping program, but I have written down the nearest named town or waypoint to a feature of interest and tracked it down in a DeLorme book or GE later on.
Udell cites Doc Searls as another window watcher. How many more geogawkers are out there?