Facebook knows what movies I like and interests I have, Spotify knows what songs I listen to, Amazon knows what books I like to read. All of these pieces of data are currently silo'd and controlled by private corporations many of which can do whatever they like with that data.
I want a private encrypted datastore that does this instead. Peer to peer so nobody controls it or can kill it. And controlled by you so Government can't get access. You set up a node and contribute CPU power and disk space. Then you get a private address and key and can push small pieces of metadata to it. This data is mirrored and very redundant so it won't disappear if some nodes go offline.
Then any site can integrate with this store. People will build libraries to write to it with various languages and others will build websites which make it easy for the layman to store and get data from it. People could create online "metadata banks" so that less technical people don't have to run their own node. Integrating with this datastore will eventually be as easy as integrating with current oauth services.
Having one global system not controlled by anyone also means there's now a standardized way for any service to request access to your data. They don't have to specifically integrate with Facebook, Spotify, Bandcamp, Last.fm etc, they just have one integration point and you can choose what data you want to share with them.
And in theory it will live on forever so as future services grow and die your data doesn't die with it.