My searching/browsing just now turned up some other interesting stuff, about using Bitcoin totally off-grid: Blockstream Satellite for receiving the blockchain as bulk data—mesh networks for anything that needs two-way communication. Will not link, because I am getting way out of my depth. I know some people who do mesh networks; perhaps I should take this as an opportunity to learn.
Now, mesh networks are definitely worthwhile. I was kinda hoping that Bitcoin would drive their development. The internet is far too vulnerable if the feds should decide to get nasty. There are some improvements that could be made to the networking layer (and, indeed, I believe that the networking, along with the wallet, should not be part of "core" Bitcoin) that could get around some of the basic blocking actions but it really needs its own physical layer option too.