Servers are easy to have at home. My mate has a small server tower with a whole bunch of hard drives in it (can't remember how many, but it's about 1000gig I think) in his home to which a bunch of us are hooked into via FTP. Really it's just data storage - movies, pics, mp3's, software etc.....

But to have a pro server at home, I dunno.... Proper servers are pretty expensive kit I think - getting it all installed and set up might cost a pretty penny!!!