Jabber + VTK = Jaivis. Jaivis is built on top of VTK (Visualization Toolkit). Jaivis uses Jabber to connect multiple VTK sessions into a multi-user interactive visualization.
Tapioca is a framework for Voice over IP (VoIP) and IM applications. Its main goal is to provide an easy way for developing and using VoIP/IM services in any kind of application. It provides a pluggable interface for different protocols, such as SIP/XMPP