This LaCie NAS is a very stylish unit, and it's positionable horizontally or vertically. It's also good value at 32p per gigabyte.
It's especially designed for FTP use and, in fact, the vast majority of operations are controlled using a web interface. It's slightly long-winded for the very tech-savvy, but it is smart and easy to use.
The 500GB capacity is made up of a single disk, so the LaCie is unable to back itself up, but you can attach a USB disk for this purpose. But bear in mind there is just one USB port, so you can't take advantage of the print server at the same time.