Alternate Browsers. I like Portable Apps especially Browsers.
Totally self contained, No install other than extracting to a Folder, No registry entries. All Favorites/Bookmark configurations, historys, temps all saved in their own folders.
Originally designed for portable devices such as Flash drives etc they run even better from a HD.
Their folder can just be copied to another drive or computer and be exactly the same. Will not conflict in any way with an installed version (same version older or newer).
A good way to evaluate before installing the Installed version (but who would want too).
I keep them all because my clients use a mixture ot the installed versions and I need them to trouble shoot and try to duplicate their issues.
Also to pinpoint issues with another browser. Have an issue with IE and the same issue exist in all 3 portables. Then it is a Web page problem. Works in the 3 portables but not IE then an IE problem.
Finished with or don't like. Just delete the folder.
And they each have some added or unique features but they all share a few features. They are all faster than IE, less targeted for Malware and basically more stable.
My favorite is portable FireFox which I use as my main browser.
FireFox
http://portableapps.com/apps/internet/firefox_portable
Opera
http://www.opera-usb.com/operausben.htm
Chrome
http://www.google.com/chrome
Mike