That's super strenght of FF, being open source, it has all sorts of addons.
That makes it the greatest browser IMO.
It will equall almost everything Opera has to offer (minus mail, actual zoom and voice) and then surpass it.
Such as:
- AIOS (= sidebar, even has Opera behavour)
- Add Bookmark Here
- ImgLikeOpera
- Image Zoom (not as good tough)
- Mouse Gestures
(you can make your own)
- Rewind/Fast Forward Buttons
- Stop-or-Reload Button
- ScrapBook
- Secure Login (=Wand)
- Past and Go 2
- User Agent Switcher
- Wizz RSS News Reader
- Web Tab Mix (customise tabbar to your heart's delight)
And ofcourse than comes the AdBlock, NoScript and FlashBlock brigade.
But I like Opera too.
Because of Mozilla, Opera is now free and has widgets, and "opera:config" and is more easy to use.
Also Opera camed with the tabs, and many, many other features now available on FF and IE.