This has been explored by Tor, through a design sometimes called "flash proxy" and "snowflake". They used websockets and webrtc datachannels so that all you ha

This has been explored by Tor, through a design sometimes called "flash proxy" and "snowflake". They used websockets and webrtc datachannels so that all you have to do to volunteer yourself as a relay is visit a webpage with JS enabled. The idea is to have many short-lived proxies on residential connections, paired with an announce mechanism.