Varnish Cache is a web application accelerator also known as a caching HTTP reverse proxy. It is installed in front of any server that speaks HTTP.
mod_pagespeed is an open-source Apache module created by Google to help Make the Web Faster by rewriting web pages to reduce latency and bandwidth.
Has anyone successfully configured Varnish and mod_pagespeed together? If so, did they see any performance improvements, and what did you have to do to get them both working?