Adds a Theme option to any active theme allowing you to make a child theme.
Useful for shared hosts, this allows you to easily create child themes from any theme just by clicking.
In the current version of WordPress, you shouldn’t modify CSS of any downloaded themes because if you update the theme, your changes will be destroyed. What you should instead do is create a child theme and edit the CSS there, this way updates to the parent theme will be inherited instead of destroy your changes. The problem is that currently the only way to child theme something is edit files on the filesystem. This is non-intuitive for shared-hosting sites with one-click WordPress installs (it usually involves a “shell account” or learning how to use FTP).
This attempts to get around that issue, by adding a button to the themes page to allow you to child theme the page. (It’s not really one-click, though.)
Inspired by @janeforshort‘s and @designsimply's WordCamp SF 2011 talk on CSS theming as requested by @sfgirl for her blog.