I took Southwest Airlines from Baltimore to Islip recently. It was my time in the relatively new Southwest terminal at BWI. Most of the gates had a power bar set up where you could plug in your laptop and work while you waited. I had seen something similar at O'Hare, but there were many more of these and they were right at the gate.
I have a Boingo on the Go account and Boingo wireless was available, so I was able to get about an hour's worth of work done. I was there quite early since I was worried about rush hour traffic and I left early. However, traffic was just fine.
I also had a good experience at the Madison, WI airport. I had a long delay, so I waited outside the security area, where they had a vary comfortable waiting area with comfortable leather chairs and plenty of power. Wireless was available, but I was surprised that there was a charge. I had seen lists of free wireless at airports and most of them were smaller like Madison.