To keep track of all items an employee is involved in we use views where items are only shown if "created by me" or "assigned to me" or "watched by me" (custom person column).
This works but I'm missing the option to add "subscribed to me" to view items were I am added as a member. This is a default feature used by many employees. It's nice for getting updates via e-mail but it would be better if this could also be used as a filter.