Created at MIT, Zephyr was designed as an instant messenger protocol and application-suite with a heavy Unix background. Using the "do one thing, do it well philosophy of Unix, it was made up of several separate programs working together to make a complete messenging system.

Zephyr is still in use today, mostly in University environments such Stanford and, of course, MIT.

Related

  • Gaim, a popular multi-platform Zephyr-capable client