[gpm]

The first thought that comes to mind is Tor's pluggable transports used to bypass censorship.

Admittedly 6Bps isn't good enough for that (I think), but it might be possible to combine it with other mechanisms or increase that number?

https://www.torproject.org/docs/pluggable-transports.html.en

[egberts1]

While TOR represent the worst kind of the variances of inter-packet delay of all network topology, the devil in the details is compensating for the largest “single-hop”-like variance.