Effective Social Business in Gov?

We've all heard plenty of examples of agencies using social channels to connect with citizens or to connect employees with one another. But, when GovLooper Katherine Ryan recently asked whether I knew of any good examples of government agencies that use social business cohesively across citizens, employees, and other organizations, I was at a loss.

Now I turn to you, the community. Do you have any good examples of agencies that are using a cohesive social approach across these three distinct segments? Is your agency coordinating its approach to multiple segments?