Hypercore Protocol: Peer-to-peer data sharing
hypercore-protocol.org
hypercore-protocol.org
As far as I know, you can't fully have both(Because of the tombstone problem and source of truth issues), but either one individually can be implemented.
True deletion, or multiwriter within one DB would have been nice to have.
Other than that, it looks to be a great thing. I think it is more practical than IPFS at the moment because IPFS lacks any top level concept of feeds or collections, just one giant DAG with random access.