I have a few favorite airports:
JVL - Janesville, WI - mainly because I worked my first FBO job there for 3 years and its also where I soloed and received both my private and instrument rating. Always have a special bond to those airports that got things started.
CGX - Meigs - Rest In Peace. Used to be so nice flying along the shore with the skyline in sight. Then landing and walking through the city to have dinner. Damn you Daley.
Bermuda International - Aboslutely beautiful island and the nicest people. The approach was beautiful with nothing but turquoise blue water in sight as we touched down. Then to have a jazz band playing carribbean tunes in the terminal just topped it all off. Definately recommend Bermuda to anyone wanting a nice vacation (although not the cheapest)
London Gatwick - My first trip overseas to London. Not a bad airport with a lot of nice shops and duty free stores. Not to mention I sat first class on an A330 on the way back to PIT. Fully reclining chairs and personal tvs ahhhh a nice way to spend 8 hrs in the air.
PIT - I have to have been there around 100 times. Every time I used my flight privelages it was my first stop before taking the fun trips. Just liked it because when I was there I was either going on a fun trip or heading back home to my bed.
SEA - thought the approach over the city was pretty cool. Plus there are plenty of aviation related things to do in Seattle with the Boeing plant and many museums nearby.
DCA - easiest place to do a day trip for you non-revers. Great views on approach and departure and they also have great transportation on sight (Metra) that gets you anywhere in DC very quickly for only $5 all day.
Alright, I think I got a little carried away since the thread is titled "favorite airport" not airport(s). Oh well, you gotta love em all.
Happy Flying!