Hokay. I’ve mangled my blog software to support tags; so now there are tags associated with postings as well as categories.
I’ve changed the display of my postings to include links to the corresponding technorati tag page; but also to a local tag page which displays just the postings in my blog that match any given tag.
Also, if you go to http://www.neato.co.nz/tag/sometag you’ll get a display of matching items.