Via funkaoshi comes a link to a Technorati Cosmos plugin for Textpattern. Combined with tag functionality, (also see much discussion at the forum and Burning Bird’s tagback effort) this plugin makes for some pretty tight integration with Technorati. (The author, whose blog is lovely and largely in Italian—which itself is lovely—has also written a WYSIWYG editing plugin for Txp. Mad skills. Abilite arrabbiarsi? Probably not quite right.)
Also on the subject of tags, Jonas Luster has lately been doing some neat tinkering: He’s using Yahoo[!]’s term extraction API to automatically extract tags from posts in Wordpress and display them as links to Technorati tags.