This would be an entertaining way of dealing with MITM agents as well, over HTTP. As long as the client knows not to open the request, you could trade them back and forth with the MITM spy wasting tons of overhead.
It would be an interesting way of streaming data if both sides used a custom decompression algorithm that skipped n bytes without allocating it anywhere.
The payload could be encrypted text of two chat bots talking jibberish.
Now that's very interesting. Maybe hack a custom ssh with this feature. Adversaries that intercepted data or attempted MitM would be inconvenienced.
Edit: Or even more useful, bbcp. Which is the best file transfer app that I've ever used.
This is similar to kippo or cowrie, SSH honeypots: