I use the SRG Clean Archives plugin on my blog but it wasn’t working under WordPress 2.3 so I hacked it and made it work, and I thought I would make it available to download for others should they want it.
Note that the official development of the SRG Clean Archives has been taken up over here, and their version works with 2.3 as well (apparently). I had a plugin that worked and couldn’t be bothered downloading another version and modifying it when a couple of hacks to the code was all it took to get the one I’m happy with up and working.