Why?

For about £200, you can have a Synology or QNAP (or other) NAS box with a few hundred Gigabytes of hard drive in it. This can be easily upgraded to higher capacities and have external backups added in a variety of configurations as your budget and needs develop. They also have built in FTP server, web server, BT downloader, scheduled backup, multi-user storage allocation management, etc.

Why should anyone want a Microsoft Home Server running in a giant box when one of these little beauties will do it all for you?