For us LA/Orange County based people, Long Beach (LGB) is really emerging as a good low-fare airport. AA just added three flights to Chicago, in addition to their flights to Dallas. On a less than 7-day advance purchase to many of the mid-west/eastern destinations I travel to, they have been almost half the cost of the same itinerary from SNA or LAX.

The airport is very small, accessable, and only has one other airline (America West) right now. I prefer SNA's proximity to my house, but LGB is only a 20 minute drive during non-peak times. LGB does not have an Admiral's Club, or very good catering, however.