Another RSVP reader, more focused on the presentation of the text, rather than many options.
Twitzer is a Firefox extension which lets you post text longer than 140 characters on Twitter.com. It also resolves TinyURL links to actual links.
Make a back up of Your weblog in WXR (Wordpress eXtended Rss) Format. So you can use it to move your weblog to wordpress OR blogger. it currently supports Blogfa, PersianBlog, BlogSky and Mihanblog.
Gmail plugin that lets you TRACK emails you've sent that are awaiting response and shows you pictures and social information for any incoming email.
receive or update sina micro-blog!
Easily access a menu displaying Firefox's keyboard shortcuts.