(previously MacPopUp) is a program that allows Mac users to exchange instant messages with other users on any local area network (LAN). With MacPopUp, you can send and receive messages from different operating systems such as Mac OS, Windows 95/98, Windows NT, Windows for Workgroups, Linux, and other Unix operating systems. MacPopUp is compatible with the Microsoft WinPopup application and similar clients in other operating systems.
MacPopUp can be used on the networks where only Mac OS-compatible computers are installed. MacPopUp features include the ability to send messages to an individual user or to a whole workgroup, and the ability to find all users available on a network. In addition, MacPopUp works in the background, supports Text-to-Speech compatibility, chat mode, drag and drop, and has an attractive and user-friendly interface.