That's amazing--I had the same luck for christmas with a flight on NWA to El Paso (to go to New Mexico). Flights everywhere running in the high 300's to 400's. And magically one day a flight around $250 (or less--forgot what it was actually) popped up on NWA. This was many months ago.
Now I'm obsessed with frequently checking airfare rates b/c you never know when one will pop up.