Automatically set the expiration date upon submission of an entry

Add a {category_count} variable to the {exp:channel:entries} loop which shows the number of categories assigned to the current entry

Make categories required for specified channels

Mobile allows you to serve up a completely different set of templates when your site is accessed on a mobile device.

Use and output many types of ranges in your templates.

Save entries for a user to do something with them on (another) page

Navigate through your entries like H. G. Wells would do