Borkware.com is hosted at Acorn Hosting, a reasonably-priced provider of virutal machines. We share the machine with a number of other folks, but we've never really noticed any performance problems. In fact, the sites are significantly faster than on our previous colocated machine. In addition to Borkware, there are a number of other sites that live on its IP, with virtual hosting described in our AOLserver Virtual Hosting with TCP rant.
Borkware and other sites are built on OpenACS 4.6.X, a very nice web toolkit based on obscure, but powerful tools. MacEdition has one of our rants on OpenACS, and there's some instructions on making it work on Mac OS X. In fact, most site development happens locally on Mac OS X, and then the packages are uploaded and installed into the site. Our home office uses satellite internet, which has high latency, which makes interactive development on remote systems inconvenient.
The Core Mac OS X and Unix Programming pages are an OpenACS package. The errata, source code, and other resources are custom acs objects that are associated with book nodes, which you can see if you expand the trees in the comments section. The tree was derived from the same SGML sources that we used to create the book, with a little tweaking to get the page numbers correct. The commentary for each book node is an OpenACS Forum instance.
This site built with emacs.