Source

Features:
- View syntax-highlighted source of the actual DOM
- View the source of selection or source of a single element
- Custom themes for syntax highlighting, line numbering, text-wrapping, click-able links
- Quick source or content editing
- HTML/CSS/JavaScript formatting
- JavaScript compression
- and more...

The functions are available through shortcuts.
For the full list of features or other details check out the preferences and the support page.
Questions and requests are preferred on support page.

Icon: http://esk6a.deviantart.com/
Syntax highlighter: http://code.google.com/p/google-code-prettify/
HTML/CSS/JavaScript formatting: http://jsbeautifier.org/
JavaScript compression: http://code.google.com/closure/compiler/