http://xbox360.ign.com/articles/834/834703p1.html
November 13, 2007 - On November 15, Xbox Live turns five years old. To help mark the occasion, Microsoft has announced several bonuses and a new feature for its over 8 million members. If you missed out on the fun of the original Xbox, it looks like you won't have to scrounge through the used games bin for a second chance.
The big announcement of the day is unquestionably the upcoming launch of Xbox Originals. Beginning December 4, Xbox 360 owners will receive a free system update when they log onto Xbox Live. Along with a number of unannounced features, this update will give players the ability to download original, full Xbox games to play on Xbox 360. Each download will cost 1200 Microsoft Points ($15 USD).
The initial release list includes Halo, Psychonauts, Crimson Skies: High Road to Revenge and Fable, as well as other as of yet unnamed titles. Microsoft has promised that this lineup is only the beginning and that Xbox 360 owners can expect to see the catalog grow in the coming year.
Microsoft is also giving away, as a gesture of thanks, a free game for all Xbox Live members. Between November 15 at 12:01 PST and 11:59 PST on November 16, all active Xbox Live members can download an Xbox Live Arcade game for free. For those in Korea, the game will be Hexic 2. The rest of the world will have the opportunity to snag Carcossonne.
If you've been with Microsoft and Xbox Live since the very beginning, you'll also be in line for one more reward. Every active member who joined the service in 2002 will be credited 500 free Microsoft Points to use as they see fit.