SatAnchor is a first—level Bitcoin protocol that turns the blockchain into a time-locked message storage and messaging layer between users. Users can block any message using BTC, which is blocked automatically when the block height, timestamp, or halving event is selected. BitMessage extends this capability by providing encrypted messages sent directly to Bitcoin addresses via OP_RETURN. No accounts, servers, or custodians - just Bitcoin, cryptography, and time.

by @Casey

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