Microsoft's pushing some new shooter franchise no one has heard of called Halo by offering up some free downloadables for Xbox Live Gold members:

All you have to do is click on the Unite to Fight ad in Xbox LIVE to get access to this content:
1. Halo 3 Theme - Available starting Tonight at midnight
2. Halo 3 Gamerpic - Available starting tonight at midnight
3. "Inside Bungie: Halo 3 - The Story" video: Interviews with the Bungie team. Available on Thursday, Sept 27
4. "Inside Bungie: Halo 3 - New Features" video: Interviews with the Bungie team about the new Halo 3 game features. Available on Friday, Sept 28
(Edit - The free content is accessed by clicking on the Ad which says "Get the Unite to Fight Exclusive Content Here". The ad which says "Halo 3 Out today/Unite to Fight Find out More Here" will bring you to the paid content section. We apologize for any confusion.)

Just what you need, a free Halo dashboard theme - so you can still be thinking about Halo in those spare seconds between when your Xbox boots and the Halo disc loads.