There is legitimate free-wifi out there, but the one Devin is talking about is caused by Microsoft's Wireless Auto Configuration (as explained in the link I posted).
But you can also tell it is not a valid access point because of the icon you see in Windows that shows it, the network shows up as an "ad-hoc" network, which is basically connections from one computer to another, instead of an access point (like a router).
If you see the the ad-hoc icon (2 computers 'beaming' each other'), don't waste your time;

I subscribed to Boingo btw, but I think I'm going to cancel it. I use it mainly for airports, but when I'm out, I like to go places like Panera to find good free wireless connections.
One thing that irks me is how many airports don't have free wi-fi, I guess I'm spoiled by Tampa International.