"I don't even like the thought that they're running some kind of hardware that makes this possible"
It's called a proxy server. They're actually really common - many ISPs use them. Any hotspot that shows a log-in page in your browser will, and I know my University's internet goes through one.
Squid [1] is one of the most well-known, and it's open source.
It's called a proxy server. They're actually really common - many ISPs use them. Any hotspot that shows a log-in page in your browser will, and I know my University's internet goes through one.
Squid [1] is one of the most well-known, and it's open source.
1. http://www.squid-cache.org