Yahoo Traffic Server
Yahoo has donated the caching proxy server they use internally to Apache Foundation. This, apart from acting as a high performance proxy server has many other cool features. If you’re trying it out here’s the minimum required settings that you should set in order it to act as a caching proxy server.
First you have to compile it from svn, or git. Info on doing this is available in the README file. After doing make install, by default it’ll be installed into /usr/local. Configuration directives are broken down into a series of files in order to make it easy to find and change aspects of the system. Main configuration file reside in /usr/local/etc/trafficserver/records.config. Open it up with a text editor and make sure that proxy.config.reverse_proxy.enabled and proxy.config.url_remap.remap_required are set to 0. Then open up /usr/local/etc/trafficserver/storage.config and configure a simple file cache. Uncomment the respective entries and make sure a folder with the name exists that the traffic server user can write to.
Start the traffic server by trafficserver start. Configure your browser to use <ip of the machine running traffic server>:8080 and you’re all set. Now you can test with the bazillion other options available in the config files.