David emailed me this afternoon asking about the possibility of listing posts in a WordPress blog that belonged in a given set of categories. So, you could list all posts that belong in both "Category A" and "Category B". Ironically, Ultimate Tag Warrior offers something like this for combinations of tags, but the native WordPress category interface doesn't seem to do it. Some way of viewing /category/CategoryA+CategoryB should do the trick.
I've been thinking about this all afternoon, and it's really starting to bug me. There must be a way to do this. Lazyweb, can you help me (and David)?