FREE WI-FI. Your move, every-other-airport-in-the-nation.
But aside from that, Phoenix Sky Harbor is a great airport. I come here about 4 or 5 times a year least and usually travel to Chicago, several parts of California, or the DC area. Okay--so I admit that there are a handful of airports with free wi-fi, but Sky Harbor is great in several other ways. Security lines are always pretty short (even on holidays, believe it or not) and parking is great--they have several economy lots with daily parking rates and a short-term lot if you're just dropping off or picking someone up. When picking people up, they give you a few minutes of waiting at the departure doors before they yell at you to move along--most airports don't let you stop unless your passenger is right there ready to get in. Also, they have a Bondurant C6 Corvette on display in the Terminal 4 baggage claim--gotta give plus points there (another terminal has an old war plane hanging from the ceiling).