SyntaxHighlighter Plugin

Tony Garcia has completely revamped his SyntaxHighlighter plugin. This version allows you to simply enter code in the text editor with the brush of your choice. This plugin should fix most of the problems people encounter when trying to use the color coding plugin (the one that comes bundled with Mango) and trying to use the HTML editor (note that you should probably disable the bundled color coding plugin).

You can read more and download from Tony's blog.