Pidgin-paranoia is a plugin for Pidgin (formerly known as Gaim) that provides information-theoretically secure encrypted conversations using one-time pads. Because the plugin uses a one-time pad where the secret key has the same length as the message and the key is only used once, the encryption is information-theoretically secure. This means that from the encrypted messages the contents of the messages are not revealed. In short: If you use truly random numbers to generate the key files, and if you keep them perfectly secret, one-time pads can not be broken.
The ipoque PRX traffic manager effectively detects and controls all major peer-to-peer (P2P) filesharing, instant messaging (IM), and Voice over IP (VoIP) protocols. Bandwidth and volume limits can be assigned to network links, subnets, individual users, and user groups. Detailed usage statistics are provided and can be exported for post-processing. This community edition is a fully functional version with a bandwidth limit of 2 Mbit/s.
MSNgrep is a script to capture MSN Messenger conversations. It uses pylibpcap to sort through MSN's jumble of packets for instant messages, a few status messages, and TypingUser notifications. Using these, it builds up a database of email addresses to MSN server addresses, and local IP addresses. This lets it match up an instant message to the sender's email address, and the receiver's email address.