I've been using Deepest Sender as my blogging tool up to now, but it always annoyed me that it didn't properly support Drupal categories (the actual category names are blank). Well finally here's a tool that does support categories in Drupal:

ScribeFire (previously Performancing for Firefox) :: Firefox Add-ons
ScribeFire (previously Performancing for Firefox) is a full-featured blog editor that integrates with your browser and lets you easily post to your blog. You can drag and drop formatted text from pages you are browsing, take notes, and post to your blog.

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