If you use Firefox or SeaMonkey as a web browser you may be interested in the ScribeFire browser add-on. It’s a pretty good basic editor for making up quick posts to your blog. Once installed in the browser, you call ScribeFire from the browser’s “Tools” menu.
Included is an account setup wizard that makes connecting to your blog simple. (For WordPress you need to first login to your admin area, choose Settings–>Writing. In the Remote Publishing Section, check the XML-RPC box.)
ScribeFire’s interface is easy to use and understand. A convenient and clear panel beside the editor window allows easy access to Blogs, Posts and Pages for straight forward review and revision. The minimal editor tool bar does include convenient utilities for adding YouTube Videos, regular hyperlinks, and images to your posts.
More information is available at http://www.scribefire.com/help/supported-services/