I bought a fancy new machine a couple weeks ago, and I must share.
I've been lusting after Shuttle's little SS51G case for a while now. It's about the size of a toaster, and comes with a small form factor Socket 478 motherboard. The motherboard has integrated video, audio, and ethernet, and there are USB and firewire sockets on the front and back of the case.
Because the case is so small, heat management is a challenge, and so Shuttle has a very cool liquid-filled heat pipe that conducts heat from the CPU to a fan on the back of the case. That fan and a small one on the power supply are the only fans in the system, which (they claim) makes it a fairly quiet system.
The small size, built-in ethernet, and clever heat management have made me eye this as a replacement for my aging Pentium-Pro 200 server (which currently runs this site). I finally got around to buying one recently, along with a 1.7 Ghz Celeron (the slowest, cheapest CPU available for Socket 478), 256MB DRAM, a cd burner, and a super-quiet Seagate 80 Gig Barracuda drive. The grand total, including shipping (from Tiger Direct): $582.
The system is up and running Redhat 8.0, and I'm in the process of migrating MonkeySpeak's services over to it. (Everything's moved now except for the websites, which are still on the PPro). It works great so far, with only two real issues.
First, it's not as quiet as Shuttle made it sound: the fans are pretty quiet, but there's a fair bit of case rattle. Pressing my hand on the case quiets it down, which makes me believe that some strategic padding may solve the problem.
If I can resolve the case rattle, I think it'll be hard to hear the machine from more than a few feet away.
Second, the integrated (SiS 651) video has had issues. In XFree86, It's only recognized as Generic VESA, and runs at 56Hz. That's headache territory for me. The image is also distorted on the edges of the monitor. I know Shuttle's early cases had video issues, but I'd heard that they'd been resolved in recent models. To be fair, I haven't spent any time trying to resolve the video issues, so it's possible that some driver fiddling and monitor tweaking would set things right.
In any case, I'm running the machine monitorless (and keyboardless and mouseless) as a server, so the video issues don't affect me at all. And if I were using it as a desktop machine, I'd probably use the case's AGP slot to put in some real video hardware. (Though I hear that the 200W power supply may not be enough for today's power-hungry video cards. So it may be this case isn't cut out for real video work.)
All in all, I'm very impressed with the system. Except for the case rattle, I'm in awe of the construction. Everything is machined beautifully, everything aligns flawlessly, and the internal layout is very well thought-out. If you're in the market for a little server machine, I highly recommend it.