If your Xbox 360 was manufactured before January 1, 2006, Microsoft's extending you an olive branch and fixing your (most likely broken) Xbox 360 for free. Microsoft says that there's been a higher than usual amount of consoles coming back for repair, something that's been talked about endlessly for the past year.
So if your machine was manufactured before Jan 1—manufactured, not bought—give them a call now.
Microsoft Compensates Xbox 360 Owners [IGN]