Facebook Unfriend Finder

http://userscripts.org/scripts/show/58852

This greasemonkey script will allow you to see when a "friend" of yours has unfriended you from facebook or deactivates their facebook account. From what I've seen so far, this script is only enabled when you log into facebook.

Grease Monkey: The most useful Firefox add-on

http://wiki.greasespot.net/Main_Page

Greasemonkey allows you to customize the way you browse the interwebs. I'll be posting useful scripts which you can use to customize how you view certain websites.

Install it here:
https://addons.mozilla.org/en-US/firefox/addon/748

Control your songs from your browser

https://addons.mozilla.org/en-US/firefox/addon/219

This add-on allows you to control any media player from your firefox browser.
This feature is currently unavailable on Chrome (or at least I can't find it)