Scribefire is a Firefox extension for blogging. It is the reason this blog exists, or at least what motivated me to finally start one.
It starts by clicking the button in the status bar:
This brings up the typing pane. I can type, close it if I need to see more of the pages I’m looking at, then reopen and continue. It offers great capabilities, most blog services, and has several really neat functions, like uploading your image to an ftp server and giving you the link.
I use it to just be able to post while doing other things instead of having to concentrate on making a post. It integrates well into other services too.
Overall, it makes blogging much easier, making it almost instant.