Firefox Add-ons? Yes, please!

Since I've upgraded to the 1.5v of Firefox, I've been going a little Add-on mad. I can't get enough of all the extras available for download. So far, I've added:

• Sage: I use Sage the least mainly because I use Kinja, I guess. But I have wanted to try out an RSS reader. Wizz RSS Newsreader is another one that I have read positive reviews about.
  
• Tabbrower Preferences: I used to have an old version with my pre 1.5v of Firefox, and loved it, so when I transitioned into the new 1.5v, I wanted to upgrade. Tab Mixer Plus is also excellent. I did download it and try it out. But I think familiarity wins here.
• Gmail Manager: I don't give people my gmail account often because it's so new, and I'm trying to limit my emailing activity to one main account, so I don't lose track of emails. But I think I might just have to break the rule on the one-email-account-only because the manager is so addicting. Nothing like waiting to see if you have mail.
• del.icio.us: I'm loving the del.icio.us extension. It beats going into my bookmarks every time I want to tag something. I have an icon on my menu bar that allows me to simply tag any web page I come across. Plus, there's even an icon that takes me directly to my del.icio.us page. Perfect.
• Answers: I've never heard of this search engine before. But their ALT-CLICK on a word to find the meaning is a revelation, and it will do wonders for my vocabulary. Usually, when I come across a word on the web I don't understand, I just ignore it, or maybe I'll be tempted to type it in my search bar and select dictionary.com to look up its meaning. But no more! Alt-Click is all that it takes.
• SearchPluginHacks: Finally, I found something to get rid of unwanted search engines. I took out Creative Commons because I don't think I'll be using it much. I did take out Answers before I knew what it was, but I think dictionary.com and Wikipedia will suffice as references. Plus, having Amazon and Ebay as search engines does little to limit the useless hours I spend surfing their sites looking for bargains and useless junk.