Here's a P2P chat application I recently created re-using the basics in the text chat sample provided by Frozen Mountain (http://www.frozenmountain.com/). Frozen Mountain offers software libraries for developing real-time applications. In this sample, I have enabled usage of Frozen Mountain's IceLink and WebSync libraries in a Unity3D application demonstrating a simple text chat among peers.
Key Technologies/Software used -
The sample requires download and execution of IceLink and WebSync servers, which are available via the Frozen Mountain link above. This particular sample was developed using the Community Edition of the IceLink and WebSync servers running on the local machine (a Windows 7 system); however, the server URLs/IP addresses may be changed as appropriate using the source code provided.
Here's a snapshot of the sample in action -