http://www.google.com/chrome

Google Chrome is a browser that combines a minimal design with sophisticated technology to make the Web faster, safer, and easier. Use one box for everything--type in the address bar and get suggestions for both search and Web pages. Thumbnails of your top sites let you access your favorite pages instantly with lightning speed from any new tab. Desktop shortcuts allow you to launch your favorite Web apps straight from your desktop.

Google Chrome is arguably the fastest web browser out there, and it's focus is on creating a minimal browser interface that focuses on the site content instead of toolbars.  Each tab is shown on top and uses its own process, so that if one crashes, the others are fine.  Google Chrome is a perfect browser for those who want speed and reliability without a lot of addons, themes, or other widgets.  This is an excellent browser for student computers or for netbooks & labs.