Hosts3D is a 3D real-time network monitor, displaying hosts & packet traffic. Features: multiple sensor support, gather hostnames & services, configurable subnetwork layout, record/replay packet traffic, filter packets by hosts, protocol or port.
This is an amazing piece of work. You can see traffic patterns and organize the view so that anomalies are easy to detect.
Why is my vote thumbs up, but showing a thumbs down?! I seriously love this project! For the record, this is an upvote, but it looks like a sf.net bug or something.