World War II shooter fans will be having a field day today, as besides Day of Defeat: Source a single player demo for Call of Duty 2 has been released as well.

You can get the demo from a wide range of sources:
3DGamers, ActionTrip, FileCloud, FileFront, FilePlanet, FileShack, GDHardware, and WorthPlaying

The demo is some 670 megabytes in size, and the hefty download includes a single mission in El Daba, Egypt, where you're tasked with blowing up four artillery guns.