I'll second that. I used one for about three years with Windows Server 2008, primarily as a NAS and for playing around with Windows domains. Cost me less than £100 (plus HDDs), held five 1.5TB hard drives, ran near silent, and was reliable.

I've also got a HP PSC1215 scanner/printer that is over a decade old and still works fine. I can't really speak to the overall quality of HP gear, but the few pieces of hardware I've used from them have been pretty solid.