mozilla firefox 2.0.0.16 / 3.0.1 / 3.1 alpha 2 / 4.0 alpha 1

Publisher's info:
Popup Blocking
Stop annoying popup ads in their tracks with Firefox's built in popup blocker.
Tabbed Browsing
View more than one web page in a single window with this time saving feature. Open links in the background so that they're ready for viewing when you're ready to read them.
Privacy and Security
Built with your security in mind, Firefox 3 keeps your computer safe from malicious spyware by not loading harmful ActiveX controls. A comprehensive set of privacy tools keep your online activity your business.
Smarter Search
Google Search is built right into the toolbar, and there is a plethora of other search tools including Smart Keywords (type "dict <word>" in the Location bar), and the new Find bar (which finds text as you type without covering up anything).
Live Bookmarks
RSS integration lets you read the latest news headlines and read updates to your favorite sites that are syndicated.
Hassle-Free Downloading
Files you download are automatically saved to your Desktop so they're easy to find. Fewer prompts mean files download quicker.
Fits Like a Glove
Simple and intuitive, yet fully featured, Firefox has all the functions you're used to - Bookmarks, History, Full Screen, Text Zooming to make pages with small text easier to read, etc.
S, M, L or XL—It's Your Choice
Firefox is the most customizable browser on the planet. Customize your toolbars to add additional buttons, install new Extensions that add new features, add new Themes to browse with style, and use the adaptive search system to allow you to search an infinite number of engines. Firefox is as big or small as you want.
Setup's a Snap
At only 4.7MB (Windows), Mozilla Firefox 2.0 takes just a few minutes to download over a slow connection and seconds over a fast connection. The installer gets you set up quickly, and the new Easy Transition system imports all of your settings - Favorites, passwords and other data from Internet Explorer and other browsers - so you can start surfing right away.
A Developer's Best Friend
Firefox comes with a standard set of developer tools including a powerful JavaScript and CSS error/warning console, and an optional Document Inspector that gives detailed insight about your pages.
Read Mail—Not Spam
Thunderbird is the perfect complement to Mozilla Firefox 2.

You may also try Fasterfox 1.0.3 which includes performance and network tweaks for Firefox. Download it HERE...

Portable Firefox 2.0 is a fully functional package of Firefox optimized for use on a USB key drive. It has some specially-selected optimizations to make it perform faster and extend the life of your USB key as well as a specialized launcher that will allow most of your favorite extensions to work as you switch computers. It will also work from a CDRW drive (in packet mode), ZIP drives, external hard drives, some MP3 players, flash RAM cards and more.
This is an unofficial package. It is an official build, but has been modified and a specialized launcher added to make extensions portable. No warranty is expressed or implied.
To install, just download the ZIP and unzip it to the root directory of your USB drive. It will create a "firefox" directory and all the requisite directories underneath. To use Firefox on your drive, launch it with the PortableFirefox.exe file in the firefox directory. DO NOT launch the firefox.exe file directly, as this will create a profile on your hard drive or use an existing one. Additionally, be sure you've closed any local copies of Firefox and that they've finished shutting down. Otherwise, a new window of your local install will be launched. This is a feature of Firefox itself to prevent multiple copies running at the same time.

Changelog:
(Mozilla Firefox 2.0.0.14)
- Crash in JavaScript garbage collector