The most current version of Proteus is 4.2.2, as of July 2011. Proteus is a free application.
It was originally developed by Justin Wood, then later sold to Defaultware.
Proteus's interface vaguely resembles that of Apple's AIM client iChat, although iChat is brushed metal, while Proteus uses the standard aqua. However, unlike iChat, it has support for multiple networks, and can also group multiple conversations in one window using tabs. Proteus fails to support some features of the AIM network, such as embedded images, and has poor support for file transfers. It also has no audio or video conferencing abilities.