I was able to find a video of it: https://www.youtube.com/watch?v=_BUg9NzdLd4 https://www.youtube.com/watch?v=_BUg9NzdLd4 I think this is the code: https://git

I was able to find a video of it: https://www.youtube.com/watch?v=_BUg9NzdLd4 https://www.youtube.com/watch?v=_BUg9NzdLd4 I think this is the code: https://github.com/paulgb/cachebeacon https://github.com/paulgb/cachebeacon It basically just runs two servers: - A DNS server that resolved a list of domains to its own IP. - An HTTP server that looked at the HTTP host and proxied requests to the upstream server. If the content type or extension indicated that the response was JavaScript, it would add the payload and set cache headers to cache as long as possible. - A special HTTP endpoint on the proxy server to capture data sent back from the payload.