When it comes to sending and receiving TCP and UDP any which way from the console nothing is more versatile or easy to use than netcat.

With a few simple commands you can use netcat to initiate chat, file transfer or even shell access in either direction between a "server" and a "client".

The tool can be set to listen or broadcast on any port and tied together with some shell-fu almost anything is possible.

Some listener favorites include cloning hard drives over a network with dd and netcat, tailing a log across the network, port scanning, IP redirecting, or even spoofing user-agents and referrers. Internet Explorer 22 anyone?

Digininja points to this great netcat cheat sheet (PDF 128K).

What kind of crazy stuff have you done with netcat? Feedback@hak5.org