Foxmarks
If you use Firefox on more than one computer, you’ll want Foxmarks. Install Foxmarks on each computer, and it will work silently in the background to keep your bookmarks synchronized. You can also log in to my.foxmarks.com to manage your bookmarks from any computer.
Forecastfox
Get international weather forecasts from AccuWeather.com, and display it in any toolbar or statusbar with this highly customizable and unobtrusive extension.
IE tab
Embedded Internet Explorer in tabs of Mozilla/Firefox
Permatabs
Adds the ability to turn tabs of your choice into permanent tabs. PermaTabs can’t be closed accidentally (even when closing multiple tabs at once), and will stick around between sessions. …
ForecastFox - Ideal for riders for planning rides and clothing for the next 48 hours. Highly customisable. Mine shows local rain, weather, temperature and wind day and night for now, today and the next two days.
IETab - opens tabs using the IE engine inside Firefox for those websites like this one used to be, that were broken in Firefox.
I have loads of customised search boxes also - Wikipedia, IMDB etc.
I use the dictionary add on, that’s great as it means I can spell check as I write, particularly useful when replying in here!
I also use the developer toolbar.
I don’t see the point of emulating IE within Firefox, doesn’t that defeat the purpose of using Firefox somewhat?
I prefer to see those sites that have been badly developed and only work in one browser (IE), if it’s important enough for me to see the content I’ll open IE 7, 6, 5.5, 5.0 whichever is necessary and look at it that way, but then I have multiple browsers installed so I can test any sites I develop. Lazy web developers annoy me intensely!!
But if you use the IE plugin you don;t need to fire up another browser. Simply click on a small icon in the corner of the window and FF will render the page using IE within FF so you keep all the other FF customisations you have utilised. Why fire up IE and lose everything FF has to offer just because a page is badly crafted?