A post over on the Major Nelson's blog shows a release date for Dreamcast title Sonic Adventure on XBLA.
The game will be available from September 15th and will cost 800 points. If you never owned a Dreamcast, this is a pretty handy chance to see why its one of the best 3D Sonic titles to date.
There's plenty of stuff listed in the post, so it's worth a gander. It does, of course, come with the usual disclaimer that "All content may not be available in all Xbox LIVE regions."