Correct me if I'm wrong, but Far Cry 1 (PC) multiplayer will continue working after the Gamespy shutdown in a few days, right? I know Crysis multiplayer will cease to work.

A lot of sites talking about the Gamespy shutdown said that Far Cry would be affected, but apparently it doesn't use GameSpy at all. Online (not LAN, you can use the same copy on the same network locally, though it does check ping) uses a form of Uplay; you need a Ubi.com account and password that you have to enter every launch, and a CD key (once per install, you need to contact GOG to get it), even to access the "join by ip" function. Ubisoft doesn't look like it's going to go out of business so using this game online should work fine for a long time, but if Ubisoft ever does go out of business or deletes/ditches their ubi.com account system then you'll have to resort to LAN tunneling software and modifying some files.