I bought a windows server box, ACER H320 I believe. It is a small "cube" case with four SATA slots (on occupied), an ATOM processor and *no video*.
I immediately installed Ubuntu Linux on it and set it up as a "backup server". The application is to back up my office machine. The server sits in another office and I backup daily, a "cron" job using "rsync".
Aside from the lack of video (what were they thinking!) I love this little box. It is compact, low power, and very well constructed.
Richard