Well, for editing I don't know but I have two friends that have networked their X-boxes to their computers. They just throw files onto the hard drive in the box and play'em on the TV. You can navigate the drive and it's folders with the remote. Actually, I think you can set it up to navigate the drives on any computer in the network, and play files from them.

If you have an up to date OS in the X-box it'll play DivX, mpeg, wmv, just about any format there is.

Best/Tommy