jM®<div class="post">Like grondilu said, encryption isn't possible.<br/><br/>It's possible to modify Bitcoin to send messages. Just create transactions that start with something like this:<br/><div class="codeheader">Code:</div><div class="code">BTCMESSAGEv1--This is a message OP_DROP </div><br/>The network will accept these, but I don't think your recipient will recognize them unless he is also using your modified Bitcoin.</div>
https://whatsonchain.com/tx/ef1b7c260b14d2be0732b9d3e89c2579bd5c5defcbbd9931ee416758656d8aec