Add code to the header and footer sections of your site on a page-per-page basis.
Add commonly seen user login links and welcome messages to the meta / utility section of your blog.
Change the internal WordPress scripts to use Google Hosted Scripts
Add your custom js and css by simply dropping your .js and .css files in the plugin directory. Handy for custom css / js additions to themes or plugin
Attach Scripts to your individual posts.
External files allows an author to insert the contents of an external file or url into a post, with the text automatically highlighted accordingly.
RSS link for this tag.