My Firefox toolbars/add-ons

This week, I re-installed my old computer at home which also means installing all programs. Among those is Firefox, and all the add-ons I use with Firefox. Here are mine:

• Google toolbar
  I use it mostly because of the great highlighting/ keyword selection options
  
• del.icio.us
  Social bookmarking - here are mine
• SEObook toolbar
  Various great tools for SEO
• Yslow
  To optimize loading times and performance of webpages
• web developer toolbar
  various great tools, nice and quick if you don't need the power of firebug
• firebug
  Lifesafer for debugging html/css
• fireshot
  Great for creating screenshot beyond the browser

What do you use? Did I miss some essential web developer/webdesigner tools?

PS: I didn't mention any twitter add-ons, mostly because I use standalone apps like thwirl or simply post from the web.