A proxy app that prints out data between a TCP connection.

You may need to tinker a bit to get the app to work for your purposes.

I built this primarily for listening to connections between game client and server.

It should work for anything based on TCP provided that you route the servers host name (not ip address) to localhost in the hosts file. On linux you can do nslookup <remote ip> to get the server hostname.

By no means is this a "silver bullet" solution, but it should work for a majority of connections that don't have odd reconnection behaviors.