The best free Editor available on the net - Eclipse.org

• ColdFusion plugin for Eclipse - CFEclipse
• Flex 3 SDK plugin for Eclipse - Flex Builder 3

Here are some cool Firefox plugins that all programmers should have

• Edit, debug and monitor - Firebug
• Free, secure and cross-platform FTP client - FireFTP
• A menu and a toolbar with various web developer tools - Web Developer

Here is a must have Internet Explorer plugin that all programmers should have

• Debug and monitor - DebugBar

A cool CFC code generator that helps reduce coding - Illudium PU-36 Code Generator

Tour de Flex is a must have for any Flex 3 developer - http://flex.org/tour

Flex 3 Style Explorer - http://examples.adobe.com/flex3/consulting/styleexplorer/Flex3StyleExplorer.html