I love my Firefox browser. I do. And the cool thing about it is that you don't need a Mac - though Macs do make all things more beautiful - in order to access the quiet elegance and ease of Mozilla Firefox. (Did I mention it's better than the browser you're using?)
Why am I gushing about a browser I've had for months and months? Well, I just added a few extensions that make my browsing experience even more pleasurable: FoxyTunes, which places the controls for iTunes (or whatever your media player) on the bottom of your browser window; Clipmarks, which lets you grab quick clips from Web pages and save them publicly or privately for later reference - and it automatically remembers the source; and the Answer extension, which gives you, well, answers - definitions and explanations for words for which you need definitions and explanations. All part of your browser.
That doesn't even begin to scratch the surface of how Firefox extensions allow me to personalize my browser and browsing experience. I also use coComment, Sage, and Scrapbook with great regularity. These extensions I use specifically for tracking blogs and comments as well as monthly archiving my own blog on my hard drive.
So I'm a nerd. But that's OK because I've got Firefox.
Embrace your nerddom. If you use Firefox, what cool extensions do you use?