Skype in the US is offering free wifi access for those travelling in the US between December 21 and December 27. The wifi access from Skype will be offered free in over 50 airports in the US.
Skype WiFi is available to travelers on PCs, Macs and iOS devices. To get started make sure you've downloaded the latest version of Skype for Windows or Skype for Mac, or have downloaded the Skype WiFi app on your iOS device. Once you have signed in with a valid Skype ID, check your wireless network connection to see if you are in a supported hotspot. It's that simple.
For more details on the service check out the Skypewifi page.
The map at the source link below is interactive. If an airport isn't on there then the chances are that it already offers free wifi access.