Say what you will about some of Treyarch's past endeavors, but there's no denying that given a robust game engine and art assets, even a hit-or-miss developer can make a solid game.
Now you can have access, too!
Graceful as ever, Treyarch is putting free mod tools in the hands of PC World at War players. The download clocks in at 1.1 GB at Fileshack, available at no charge to registered users (registration is free, also).
Maybe now we can get a mod that lets you save your local co-op game...