At this German site, www.deltatronic.info, they build/sell a 360 Watt(!!) Fanless ATX PSU with Active PFC. It is a serious looking device covered with heatsinks, sort of like a macho car power amp. The bad part is that it's 295 Euro's!
Deltatronic also offer a serious liquid-cooled version of the aluminum cool & quiet drive sandwich idea written about by MikeC. Again, with grooved ribbed heatsinks on the top & bottom as well as side rails, the device looks like a high end car amp.
The site is in German; Google does an OK translation.