Here is a list of my currently installed, and most beloved, Firefox extensions. Not all of them are currently out-of-the-box compatible with Firefox 3.0 RC but using the Nightly Tester Tools i can override the compatiblity check, and install them anyway. To my knowledge all of the extensions are working perfectly with Firefox 3.
- Better Gcal
- Better Gmail
- Dictionaries (Danish and English)
- FEBE (Firefox Environment Backup Extension)
- Nightly Tester Tools
- PDF Download
Hope you can use some of them and let me know if you have trouble with the links, or getting them running.