Blockchain DB allows you to leverage the blockchain as a redundant message / data archival system. Just enter your text (or raw bytes, if you preer to store data), pay the fee, and it will be embedded into the blockchain.
It uses OP_HASH160 so the data cannot be pruned or ultrapruned - guaranteeing that your data will forever remain on the blockchain. It's also completely uncensorable.
http://blockchain-db.com/ok..
but with this solution,
what size would reach the blockchain ??
i think no GB... but PetaByte...
and how you will be able to download an sync with him?