Social Source Commons

Inspired by EtherPEG (though, not owning an Apple Macintosh, I've never actually seen it in operation), Driftnet is a program which listens to network traffic and picks out images from TCP streams it observes. Fun to run on a host which sees lots of web traffic.

IPTraf is a console-based network statistics utility for Linux. It gathers a variety of figures such as TCP connection packet and byte counts, interface statistics and activity indicators, TCP/UDP traffic breakdowns, and LAN station packet and byte counts.