requires 128MB of free space, Microsoft is offering a storage solution for those who may lack the proper storage with either (a) a free 512MB memory unit or (b) a 20GB hard drive for $19.99. If you purchased an Xbox 360 console with no memory solution (i.e. no hard drive or memory unit), you can enter both the 12-digit serial number and the 12-digit Console ID here to see if you're eligible for the offer. We're not sure if there might be an issue with replaced Xbox 360s and proper serial numbers; if you're one of the eligible few, let us know your experiences in the comments below.
[Thanks to everyone who sent this in!]