Here are Firefox extensions I use, if you have some good ones that I misses please feel free to suggest.

 
Must-have Firefox extensions:
del.icio.us
Scrollbar Anywhere
Download Statusbar
Tab Mix Plus
Nightly Tester Tools – enable uncompatible plugins
AdBlock Plus
Adblock Plus: Element Hiding Helper
 

Anonymity and security Firefox extensions:
No Script
Cookie Button
BetterPrivacy
 

Advanced surfers addons:
GreaseMonkey
Extended Statusbar
ScreenGrab
Diigo: Web Highlighter and Sticky Notes
Better Gmail 2
Digg Firefox Extension
Dugg mirror
URL suffix
FlashGot
ScrapBook
SwitchProxy
DownThemAll!
 

Interesting addons:
Fasterfox
Image Toolbar
Clipmarks
BugMeNot
StumbleUpon Extension
 

Addons for blog writers:
ScribeFire (previously Performancing for Firefox)
Deepest Sender
 

 
Quick tip to see which are the biggest currently installed packages on your Fedora box:
rpm -qa --queryformat '%10{size}-%{name}-%{version}\n' | sort -k1,1n
 
You might also be interested in fslint:
yum install fslint
It lists packages by size, and it will autoselect dependencies for packages you want to delete
 

 
I would like to upload geotagged photos via my Nokia N95 and every guide on the internet suggested installing Shozu.
 
There are a few issues with Shozu:
- it doesn’t add exif tags to jpeg files!
- it adds geotaggs only when uploading to flickr
- it isn’t free
 
Nokia actually made an application that fixes this but it is quite unknown.
 
Just download and install Location tagger.