OK, I admit it, I'm hooked. Somehow I just can't keep those fingers away from usenet, despite all its many faults.
I have web pages about:
I have been a fairly active participant in net.* although it is more dormant than active (there if we need it, but not at this moment serving any need not handled by other hierarchies).
OK, partly for my own reference here is an alphabetical list of a few usenet hierarchies with web pages. There are lots more at Dmoz.org.
Anyway, my list: