MSN
MSN is a Instant Messaging protocol used by the popular Windows program MSN Messenger.
The protocol is highly insecure and can easily be monitored by third parties. In addition, Microsoft reserves the right to monitor your chat. From their terms of use: However, we may monitor your communications and disclose information about you, including the content of your communications, if we consider it necessary to: (1) comply with the law or to respond to legal process; (2) ensure your compliance with this contract; or (3) protect the rights, property, or interests of Microsoft, its employees, its customers, or the public. Take special note of how they cleverly state that we consider it necessary .. protect the rights, property, or interests of Microsoft - which is basically another way of saying if we feel like doing so, we can and will.
[edit] Using MSN on Linux
Linux-users can use the following programs to communicate with the MSN protocol: