Xbox -> Hacking -> Software -> Dashboards -> Avalaunch:

Avalaunch is a dashboard replacement for the Xbox game console. It provides new functionality to the Xbox such as a "skinnable" interface that lets you control how your Xbox looks and feels. Down to downloading new skins from online websites, the ability to download saved games from www.xbox-saves.com, and access to the XLink KAI (*free*) gaming network through an integrated interface.

Official Avalaunch Website∞