If you fly continental frequently, and there are empty seats in first class... and you have the most miles of anybody on the plane... they upgrade you for the same cost as coach.
Thankfully I dont have to fly frequently. I do have a rule If its a ten hour drive or less Drive it.
I am 2 hours from the airport. You are supposed to arrive 2 hours before a flight , add another two hours flight time and half hour waiting for baggage, then an hour getting to where you want by rental car and it just isnt worth it to fly for a ten hour drive. Add in that sometimes the plane is late leaving or the flight gets cancelled or the plane sent somewhere else to land because of a thunderstorm and its just not worth it.