Firefox!

I'm fairly confident that a good chunk of my "audience" is using Firefox and not Explorer, so how 'bout some sharing of useful extensions?

My most (or should be most) used:

• copy url+ --allows copying of text, page title, url in one (right) click
• fireFTP -- ftp client
• tinyurl creator -- convenient access to shortening long urls
• blog this -- direct link to blogger for postings
• flashblock -- makes flash windows clickable rather than automatic, for faster page loading (a little ambivalent on this one)
• mail notifiers -- for whatever mail client you use
  
• foxy tunes -- provides menu for control of itunes from browser
  

And while not an extension per se, I'm also a big fan of adding search engines to the search bar.