I'd guess it's $300-$500/mo since it's just on one server last I saw. It's a relatively simple site, running on a very fast language (Arc->MzScheme), with libe

I'd guess it's $300-$500/mo since it's just on one server last I saw. It's a relatively simple site, running on a very fast language (Arc->MzScheme), with liberal use of caching. There really aren't that many sites you couldn't run off a single server if you really wanted to. A really beefy server today is more capable than a dozen from just a few years ago.