Authenticating proxy? No thanks.

I've finally solved one of those annoying little problems that are an annoyance to hackers everywhere. Me especially. Namely, authenticating proxy servers. A lot of apps don't have support for these little fuckers (rubygems I'm looking at you) and it causes all sorts of heartache and pain.
Well today I got sick of it and decided to put an end to the madness.
First, we'll start out with an fresh install of squid. I've used the default Ubuntu configuration as a base.
The following lines are the most important here (numbered because of line wrapping):

1. cache_peer $PROXY_IP parent $PROXY_PORT 7 login=$USERNAME:$PASSWORD proxy-only no-query
2. acl all src 0.0.0.0/0.0.0.0
3. never_direct allow all

Port 7 (echo) is used if the parent proxy doesn't understand ICP. However we use the no-query option so it doesn't matter what goes here. Everything else is pretty much self explanatory if you RTFM.
Of course, not only does this configuration mean apps that don't understand Proxy-Auth can work now, when the powers that be force a password change onto you there's only one file you have to edit. Hurrah!
Enjoy :-)