I&#x27;ve been thinking about this lately, and it seems that you could use something like a book code.  Client and server use existing internet accessible images as the book and then your communication simply references bytes in those images: client requests a URL that encodes the bytes it wants to send, server returns HTML containing the urls of images containing the bytes it wants to send in response (and any extra content that helps make the page seem normal, ignored by the client).  Pictures could be anything anywhere (lolcats, wikipedia, etc.), client should only ever need to download the picture once. Bandwidth wouldn&#x27;t be great, but if the server is accessible via a wide (and evolving) variety of domains it seems like it would be quite hard to distinguish this from normal browsing.