If you have a mind to comment on posts to any number of blogs and you need to add links to enrich what you have to say, a handy tool is ScribeFire. Its' a FireFox add on designed as a blog editor. But really with the edit attributes offered by Blogger and Wordpress now you don't really need to use it for that. But for HTML editing it's handy to have it as a one click option built inside your Firefox browser. Its' also an easy way to learn HTML.