I’m VERY interested in the ReadyNAS PRO, but they just came out, so you can’t get them on Ebay yet except new ones. Then Netgear doesn’t really want to sell them diskless, so it costs almost as much to get a diskless one as a minimal configuration like (2) 500gb disks, so you might as well take it with the disks, take them out and use them for low end desktops, and put your own disks in the shell. But it’s still like $1600-1700 so it’ll really put a dent in the budget.
http://www.youtube.com/watch?v=XIMZkSVk03E