My friend has a very low data allowance on his internet plan, and mentioned he was using a German compression proxy to compress website data upstream. I thought that it should be possible to set up my own compression proxy on a Raspberry Pi, and after a bit of research discovered ziproxy. Installation on Raspbian was simple:

sudo apt-get install ziproxy

I then opened the configuration file in /etc/ziproxy/ziproxy.conf, and tweaked a few things.

I changed the port to something slightly less obvious.

I enabled TransparentProxy (although I’m not sure that I needed to…)

I set the AuthMode and AuthPasswdFile.

/etc/init.d/ziproxy restart