Announcer: "...Number 3, in a quantum finish!"
Farnsworth: "No fair! You changed the outcome by measuring it!"

You can definitely have a full-fledged linux environment on one of the DNS-323 or DNS-321 NAS units from D-Link. Basically you just drop 1 file into your root directory, reboot, and you have telnet access. From there you can pretty much install anything in the repository of pre-compiled binaries. I switched from a 4-bay server tower to this little NAS about a year ago, and I haven't had any issues. I eventually want to get another, though right now I don't have the need. See http://wiki.dns323.info/ for info.