Set up custom percentage-weighted tasks that users need to complete before their profile is considered complete. A sidebar widget is available to show users how close (or far off) to account completion they are, encouraging them to complete the remaining tasks and create a more engaged user.
The following tasks are available out of the box:
User has set an avatar.
User has set a signature.
User has entered a value for a particular custom field.
User has linked a particular connected / external account.
User has created a thread in a particular forum.
User replied to a thread.
User has verified their email address.
The add-on is also fully extensible allowing other add-ons to add additional tasks of their own.