Not that experienced with servers but they are designed for maximum performance and reliability, not really for home use. Can you put it in a room as that is what they are designed for since noise wasn't a big problem as that's the fan keeping all the high performance comonents cool.
It's a 1U server, so it's going to be hair-dryer loud with any kind of air cooling because you are forced to use teeny tiny super-high RPM fans due to the short 1.75" case height. You pretty much have two options to cool it down. The first is to swap the CPU's passive heatsink with a water block and water cool it with an external pump, reservoir, and radiator. The second option is to buy a taller case like a 4U and try to find a taller actively-cooled heatsink with a larger, slower-spinning fan. I'd probably go for option #3, which is to get a newer server as the 500 MHz CPU in that machine is roughly as fast as a PIII or an original Athlon. You do give up the coolness factor of running a non-x86 machine, but you'll be able to get a much quieter machine from eBay or a surplus store for pretty cheap.
The post is almost a month old but for reference:
I have one of these servers sitting under my couch.
These are designed to run in an environment where the temperature is high, so you can buy 2 potentiometers (a.k.a fan controls) for 2€ each and get a cheap silent server with an electric consumption well under 40W (yes 40W, electricity is not free as you know ...): at 5V the temperature remains acceptable.
I run OpenSolaris b129 with 2 mirrored hard disk drives of 40GB (ZFS inside) to serve a scientific publications database and some personal websites.
Memory usage is about 360-380Mo (including ZFS cache, nginx, mysql and friends) so there's enough room and responsiveness is good enough (i performed some benchmarks: the 650MHz in 32bit mode is roughly equivalent to a 733MHz - 800MHz PIII Coppermine depending on the task and about the same as the 1GHz PIII Mobile Tualatin based laptop it has replaced, 64bit not tested).
A nice and reliable machine as other SUN's.
Somebody has successfully installed a VGA card fan on the CPU (Zerotherm gx710) and i have tested a modified Zalman VF-700.
It's cheaper than Atom-based solutions and sufficient for my needs.