How do I detect bandwidth hogs?

[GVJosh]

While I have 4 pfsense boxes throughout the company, we are still using a watchguard devices as our primary firewall / edge device.  I plan to replace the watchguard with a pfSense box here shortly, but have a question about tracking bandwidth hogs.

For example, our WG device has a feature called Host Watch.  This lets me see nearly every connection coming/going from the router.  Here is a screenshot of what it looks like:

I've searched the wiki, pfsense itself, and cannot find a utility like this to see connections.  My question then is, how can I detect a bandwidth hog so I can walk to their desk and confront them?  I understand how to use shaping on the device but if I wanted to do this, how would I go about doing so?  Thanks for your time and consideration of my question.