We had a close look at the Windows Home Server (WHS) back in April, groping all its sweet, sweet home server features before we were shooed away by Microsoft's people. Good news for PC enthusiasts who want to do their serving from an old PC: Microsoft's just announced that they're going to release WHS as an OEM product.
What does this mean to you? Well, unlike CableCARD OEM, you can purchase an OEM version of WHS and install it on an old machine you have lying around. Seeing as it's a headless server—meaning there's no monitor and no direct input—the processing needs are much less than a standard desktop.
But, if you have more specific needs, you can still buy pre-made and customized home servers like HP's MediaSmart Server or the Medion Home Server.