There is an
xfinitiwifi hotspot near me.
Comcast users ("slaves"?) can connect to
xfinitywifi by entering their Comcast email and password on the browser redirect. Then it will record your MAC address and let you access later without the popup.
But the weird thing is, every time you login you get the IP address
192.168.1.10. Even if you login with multiple devices. (Also documented here: http://forums.comcast.com/t5/Home-Networking-Router-WiFi/What-Prevents-Xfinity-WiFi-Hotspot-Spoofing/td-p/2113294 )
How is it possible to have an access point reuse the same IP address for each client?