I just finished writing a Sherlock/Mozilla plugin for Technorati (zip, gzip). Although my sidebar item code works in simulation it breaks in Mozilla 1.7.3 and Mozilla 1.8 alpha 4. The same sidebar sends my next results code to Ask Jeeves for some odd reason as well.
Unzip the archive to your “searchplugins” directory under the Mozilla or Firefox parent directory. You should have two files: the source and a PNG image. To make Technorati your default search engine in Mozilla you need to select it from the drop-down list under Edit -> Preferences -> Navigator -> Internet Search.
Once you have added Technorati to your list of Mozilla search engines you should be able to perform a Technorati search using the Search Panel sidebar (F9).
You can pass keywords or an URL.
The same plugin is supposed to work with Sherlock 2. I have Sherlock 3 and because Sherlock 3 uses a different structure I am unable to test Sherlock compatibility. If you are using Mac OS 10.2 please try the code in Sherlock and let me know!