UCSniff is a VoIP & IP Video Security Assessment tool that integrates existing open source software into several useful features, allowing VoIP and IP Video owners and security professionals to rapidly test for the threat of unauthorized VoIP and Video Eavesdropping. Written in C/C++, and available on Linux and Windows, the software is free and available for anyone to download, under the GPLv3 license.
A wiki that documents vendors of surveillance, wiretapping, and interception technologies, what their products are capable of, and the countries that buy their gear and what they use it for. Also discusses some of the issues surrounding large-scale communications interception.