Xbox Live addicts the ability to connect to their account and do pretty much everything you can think of. Bad news: it isn't free. The $1.99 app, called 360 Live, lets you sign into your account, browse and respond to friend requests, check messages and even creep your friend's Gamercard on the go.
But, before you slap your $2 on the table, we'd recommend you wait for Microsoft to respond to the app's list price. In August 2008, Microsoft mandated that all Xbox Live-related applications be free. So, it may just be a matter of time before the 360 Live app drops to the easy-to-swallow price of free.