I'll give PIT a vote as one of the best. Its layout is great for easy connections and the shopping mall is a great time killer between flights. You can even rent a pair of shorts and a towel for a workout and shower between flights if you have the time.

I have been to a couple of smaller airports I like too. They are HSV (Huntsville) and CID (Cedar Rapids), they don't have much air service but they are modern, clean and you can be off the flight and driving away in your rental car in five minutes.

Jay