First to mind must be Trevor Parsons whose work on the London Cycling Campaign in Hackney's site is a joy to behold. Trev brought in the free internet utilities like Netmind and eGroups to increase the usefulness of a site as a tool for communication amongst activists. It works, it's updated regularly, (and when it is we all know immediately), and Trev does it all. Hats off to him.
What I really like about Ross Anderson's work is the way he places his links. The text is well-written--it would work flat--but his link-placement means that judging what is behind is highly intuitive. And if you stick around you'll find out more about computer security than you ever wanted to know.
Eric Raymond's text The Cathedral and the Bazaar is a masterly polemic that argues that not only is free software ideologically purer, but it's stronger as well. He's a cool guy at opensource.org. His annotated version of the Hallowe'en papers (a Microsoft internal analysis of the threat of open source software to its fortunes) is also highly instructive.
One of my favourite applications on the Mac is Stickies. The guy that wrote it is called Jens Peter Alfke. This is a nice home page that we could all learn from.
It's one of those amusing quirks of modern life that alternative websites make it to the web before official versions. Helen King's alternative Knowledge Managment website accurately reflects the collective concerns of our colleagial existence: the arrival of the sandwich man and emailed jokes. And hey, I'm sure the official site'll be along any day soon :-)
There are millions of people out there who use HTML, but very few write hypertexts that work. I may not know much about hypertext, but I know what I like. If I try to boil any of it out into some unifying principles (always a dangerous activity) the characteristics that these authors share are: a clear message or purpose, the ability to define that in text, and the ability to personally execute it in the medium. Most readable writing has one author, with all that it brings. Hypertext seems no different, though it is easier to cite your collaborators, and for the reader to form a judgement about the influence they have had.
Discontinuous search engine jumps over flat files are fine as they go, and just about bearable for technical subjects, but what you really want is an author. Come back to me after you've checked out the links and tell me what you think.