XPort 360 is a backup and restore utility for the Xbox 360. It allows you to navigate the file directory of the Xbox 360 memory units. The console uses both a hard drive and memory cards to store important information. Xport 360 can access both. It also allows you to "inject" information into any directory of said memory units. Using this app, you can backup game saves, demos and even updates, or move them from your PC to the XBOX if you don't have XBOX Live.
The Xbox 360 uses a non-standard hard drive format to prevent users from tampering with the hard drives and memories. Up until recently, one had to buy the Microsoft Migration Kit to even have access to the discs. Applications like Xport 360 allow you to use any USB SATA to IDE enclosures to gain access to your drives. Xport 360 comes with such USB solution. But you can use the application that comes with it with any USB enclosure.
An alternative to Xport 360 is Xplorer360, but the latter is very buggy and, to be honest, dumb. Xport 360, on the other hand, does a great job of recognizing the discs and memory cards. It allows you to completely back up a hard drive to your own computer and to move data back and forth. In my tests, it seemed to be faster and more responsive as well.
You can download Xport 360 without buying the Xport 360 enclosure, which is around $65.