Just to get it out the way, first of all, I love Firefox. It's tabbed browsing functionality has changed the way I work, and it has been a valuable contribution to the open source community.

Now, what's a plugin? For those of you who are not familiar with plug-ins, the open source status of Firefox means that anyone can access the underlying code that makes it run (which is cool, trust me), and therefore, programmers can develop their own tweaks and addons in their free time to firefox that make our computer lives easier.

For me, my add-on of choice is the Download Status Plugin. Essentially, what this did is remove the download status pop-up window that was constantly getting in the way, and replaced it with an intergrated status bar at the bottom of my browsing window. Now, I can keep an eye on my downloads without battling with a pop-up window.

There are hundreds of addons for Firefox, and you can find everything from Forecast Fox, which lets you keep an eye on the weather from your browswer's status bar, to FoxyTunes, a music manager. Check out all the available addons: https://addons.mozilla.org/en-US/firefox/