Genius Thunderbird plugin that sets a custom From address based on the recipient address of the email. Genius, exactly what I've been seeking for years. Now to get it setup...
Download apks of mobile firefox directly and skip the Google market bs. Very useful, was a pain in the ass finding this.
Jetpack is a simple language to write almost on-the-fly Firefox plugins. Pretty amazing technology, looks like css / jquery with some custom methods. Beautiful. Hat tip sfllaw.