Browser Information
This script does a great job of displaying information about your web browser.
Browser Properties
Find out the code name, color depth, platform, if java is enabled, resolution, ip address, hostname, and more.
But It Worked In Netscape?
Making JavaScript that is compatible across multiple browsers.
Dueling Event Models -- A Cross-Platform Look
The JavaScript Apostle looks at how to make JavaScript work with both Netscape and IE.
JavaScript Version
Neat little example which displays what JavaScript version the visitor's browser supports.
Making Stuff Fly
Nadav Savio explores and explains some Microsoft and Netscape differences in Dynamic HTML.
Platform Page
Do you maintain a different version of your site for Windows and another for Mac users?
Plugin Page
If you maintain separate pages, one plugin enhanced, the other not, here's a simple way to send your visitors to the right page automatically.
Resolution Page
When users visit your page, JavaScript will determine their screen's resolution and redirect them to the page of your site that you wrote for that screen size.
Right Browser?
This script will tell users if they are using the right browser and the right version.
Safe Colors
This script will show you all the "safe" colors, the ones that show up the same for all browsers and platforms.
The New JavaScript Standard
Dan Shafer talks about the usefulness of ECMAScript.
Elsewhere on About.com 
