2 Billion Add-Ons Downloaded by Firefox Users !!!
Mozilla has put up a "Best of 2 Billion Firefox Add-ons" list based on feedback. There are 25 add-ons in the collection, with the top one being Adblock Plus.
With Firebug a well deseved being ver near the top, IMHO
What is your top FireFox Add-on? Maybe it's Destroy the Web