I think that the U-NAS guys have two lines going, their own chassis (which are probably just a variation of the ones they make for QNAP) and their own NAS linux distro which they seem to sell on their site. They seem to sell their 4-bay model bundled with the OS and hardware but I don't think the 6 or 8 bays are available with it.
FWIW their bundled 4-bays come in SKUs with either an atom or a celeron proc, although not sure why you wouldn't just buy the case and build your own...
FWIW their bundled 4-bays come in SKUs with either an atom or a celeron proc, although not sure why you wouldn't just buy the case and build your own...