Processing emails with attachments

When I look through the settings TAB it seems to indicate that I can apply a rule to process an email attachment based on the file extension. i.e. detatch all .pdf files into a specific folder on a network drive or detatch all word files ( .doc) into a different folder on a network drive.

However I can’t find how to create the rule/action/task

Could you give me a reference to the page in the manual that explains how its done or alternatively answer with an example.