I'm thinking however of modifying the client to selectively store incoming OP_RETURN data (selective pruning). However, this seems, every second that passes by, more and more like an impossible task given the state of the Bitcoin blockchain and the structural integrity of conventional Bitcoin blockchain.

Selective blockchain storage seems to be against some critical principles of the blockchain itself. Ethereum is just so cool when it comes to using a different blochchain model to establish a blockchain which can be trimed, let go, reorganized or forgotten.

None the less, I'm still experimenting in the controlled coin space to establish a client which reacts to incoming OP_RETURN data off a blockchain. Namecoin does a great job at storing this sort of data, I may even use it as a base. Not sure yet though.


Cheers, thanks for the comment.