I used to load up with extensions, and I had a lot of stupid ones, but now I prefer streamlined. I use the MostlyCrystal theme and have given myself some more viewing space by switching to the top-right Googlebar as opposed to the one that had it's own bar below Favorites. I run FireFox 2 (FF3 was fail)
Here's the short list of extensions:
IE Tab (I don't use it very often, but it comes in handy. Embedded IE tabs are nice)
Google Notebook (I've abandoned my old "favorites" with the exception of the bookmarks toolbar, and use this to save important things. I make a habit of deleting old entries.)
DownThemAll
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