Rated 5 out of 5 stars
It also works on new Firefox 3.6 too.
Just use info provided in these reviews how to hack it to work on new versions. (alternatively if you want, file on that download link of mine was updated ( http://www.box.net/shared/3j18pgl3r6 ), just re-download. I also took the liberty to fix the initial window width size problem which appeared on 3.6)