Another vote for Southwest but for different reasons. I did this using the web specials (around $50 each way + tax). BA were 4 hours late. This meant missing the last Southwest of the day.

Even with fixed web specials if you turn up less than 2 hours after flight departure they will put you on the next flight without question subject to availability. Being totally outside that window I thought I had simply lost the ticket totally. In fact with my next Southwest booking by typing in the PNR reference of the flight not taken I was fully credited with that amount towards the next purchase ( I had been advised of this facility when I contacted them)

So go Southwest.. You simply cannot lose !!

Santa