Tsung is an open-source multi-protocol distributed load testing tool and a mature project. It's been available for about 10 years and is built with the Erlang system. It supports several protocols, including the PostgreSQL one.
When you want to benchmark your own application, to know how many more clients it can handle or how much gain you will see with some new shiny hardware, Tsung is the tool to use. It will allow you to record a number of sessions then replay them at high scale. pgfouine supports Tsung and is able to turn your PostgreSQL logs into Tsung sessions, too.
Tsung did get used in the video game world, their version of it is called uTsung, apparently using the uLink game development facilities. They even made a video demo of uTsung, that you might find interresting: