A blogging tool and browser in one.
Flock is a free, open source web browser. ...we've started with integrating tools that make it easier to blog, publish your photos and share and discover things that are interesting to you.
I heard about Flock months ago and my first thought was "forking firefox's code base is a bad idea", but I just fired it up and it is a wonderful experiance. Flock is a modification of FireFox that extendes the browser to be a fairly robust web editor. Flock uses web APIs to give a user a client application that for multiple web applications: Flickr, Blogging and other "Web 2.0" services.
I think Flock is a wonderful take on giving editing tools to a user.