x11vnc allows one to view remotely and interact with real X displays (i.e. a display corresponding to a physical monitor, keyboard, and mouse) with any VNC viewer. This project provides pre-built binaries, see LibVNCServer for the x11vnc source code.
H.323 Beacon is a tool that can be used to measure/monitor/qualify/troubleshoot performance of H.323 Videoconference sessions both at the network and at the host by using a end-node(client) and core-node(server) architecture.