Here are some more of my favorite Firefox add-ons:

• All-in-One Sidebar: I guess the name says it all, no more dialogs.
• ChromaTabs: Tints browser tabs with a color specific to the website loaded.
• Download statusbar: View and manage downloads from a tidy statusbar – without the download window getting in the way of your web browsing.
• Facebook toolbar: What can I say, I’m an addict.
• iGoogleBar: adds Google Apps favicons to the Google Apps Bar.
• Resizeable textarea: It lets you resize most of those textareas.
• URL Fixer: corrects typos in URLs that you enter in the address bar.