What is BlogThis! ?

BlogThis! is an easy way to make a blog post without visiting blogger.com. Once you add the BlogThis! link to your browser's toolbar, blogging will be a snap. Or rather, a click. Clicking BlogThis! creates a mini-interface to Blogger prepopulated with a link to the web page you are visiting, as well as any text you have highlighted on that page. Add additional text if you wish and then publish or post from within BlogThis!

visit to : http://help.blogger.com/bin/answer.py?answer=41469&topic=12463