You might have misunderstood. I meant that ecash sat can be used as a postage stamp.
Relays receiving the stamp can verify it is a real sat by redeeming the ecash stamp at the mint for LN sat, and then forward the message. 
Discussion
Ok took it, So one sat for relay for message. That's becoming expensive. I value privacy and freedom too, but not so rich. A feature like that is for very important messages.
Maybe spending 90 cents a month shouldn't be too expensive?
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