SyntaxHighlighter https://github.com/syntaxhighlighter/syntaxhighlighter
Google Code Prettify https://github.com/google/code-prettify
Highlight.js https://highlightjs.org/ https://github.com/isagalaev/highlight.js
Prism.js http://prismjs.com/
jQuery.Syntax http://www.codeotaku.com/projects/jquery-syntax/index
rainbow https://github.com/ccampbell/rainbow https://craig.is/making/rainbows