Here’s something I’ve been looking for for a while now: Blogarama, a directory of weblogs. I’m not sure how good it is yet, but it’s a start. And it appears to be developed in PHP, which is always a good thing.
Their categorizations could use some work, but I imagine it’s rather hard to nail down a particular blog into a particular category—especially since most blogs already have their own microcosmic taxonomy. We’ll see what comes of it.