Useful Firefox Add-ons

Here is a list of some very useful addons for FireFox (get it free here), listed in order of usefulness:

• SEOQuake - View the Google PR, Alexa Rank in this bar; the number of pages of this website that are indexed in Google, MSN and Yahoo are shown all at once.
  
• Cooliris - Preview another page from any page.
  
• AngleBracket - Get notified of new AngleBracket posts and breaking news from around the world, includes webmaster links. Customizable to include weather forecast, email notification, gadgets, and more
• Google NoteBook extension - Take notes to your Google NoteBook from any page.
• Measureit! - useful for measuring your screen in pixels
• IE Tab - View webpages with MSIE that is embedded in Firefox. Very useful for checking if pages work in both browsers
  
• FireBug - Error console with editing and debugging abilities
  
• ColorZilla - Advanced color picker letting you revealing the color code for the any element on the screen
  

firefox extensions