I've ordered 2 x Biostar small form factor style cases and all the components to go with it. They're for work, as I've been requested to build 2 new PCs for the Internet cafe next door.
Why am I telling you? No particular reason, but I'd highly recommend a small form factor chassis if you're looking for a small and quiet, yet powerful alternative to the hulk that is a desktop PC.
Sure, they've been out for a good few years, with Shuttle pioneering the market. But Shuttles are expensive for what they are, and you can get a much cheaper alternative that performs just as well, if not better.
I've built an AOpen X-Cube here recently, and am just about to embark on these two Biostars. AOpen make several high quality SFF base units, that are almost half the price of a similar spec Shuttle. I'm not dismissing a Shuttle, on the contrary. But if you're looking into building a SFF, then don't limit your choice to just the one manufacturer...