The mapz blog has a great post on mapping-related extensions for Firefox 2.0, and a single extension you can download and install that incorporates all of them.
Related posts:
- Mini Map Sidebar Firefox Extension
- In-Browser Web Page Image Capture
- Intro To GIS/Mapping For Non-Profits (And Everybody Else)
- Beta Version Of DNRGarmin
- Free ArcGIS Extensions For Municipal GIS Applications
- WMS Inspector Extension For Firefox
- GIS Video Series From Vassar
- Additional Color Applications For Maps And Design
- Obligatory Chrome And Photosynth Review
- Thematic Mapping Engine API For Displaying Your Own Data In Google Earth
