frontend_content_saved
frontend_content_saved is a hook which is runned every time when the administrates creates a new Frontend's content. This is a very useful hook if you're using the cache feature. It will let you know when the cache should be deleted. Also, it could be used in the themes to change some options.
When the hook frontend_content_saved is called, all registered hooks will receive the parameter content_id. You could use that parameter to delete cache or change the options.
For example, i'm using it with the Quick Guides in the CRM collection. It deletes the cache when the content is saved for the Quick Guides contents category.