The problem is to make a block chain so I can say I've made a block chain.
I want to climb that hill because it's there. But you're right, I need some context or application or end point. I could gamify this somehow (would be a dull game but it's an exercise) and we're right back where Slime suggested - a solution looking for a problem!
Let me waffle:
I'm actually super intrigued in hostless networks. Or peer-to-peer. I can envisage a persistent game universe existing across a P2P network that grows perpetually as long as there are peers and dies a natural death when the universe is stale and has run it's course. If we ignore the transport protocol/mechanism/networking challenges (tcp/udp/enet/sock/sockets etc) for a moment and think about the universe. Multiple players interacting across a P2P network simultaneously with no host and no single source of truth might be possible if the universe is transaction based (not a real-time shooter) with a robust block-chain (or chains) underpinning the persistent universe.
Think about a transaction based strategy game with a persistent universe. Players submit transactions to the block chain of a long period of time and with robust merging and conflict resolution across a P2P network you would have a persistent universe that has no infrastructure/server/database costs and will survive for as long it has clients. Maybe some real-estate tycoon game or some political global strategy game. Might be lots of examples.
Now, that is super super super ambitious and I'm sure people smarter than me have tried but that won't stop me trying and learning
Step one - prove I can make a block chain
Step two - prove I can make it robust (conflict resolution etc)
Step three - find a way to transport it P2P (another bucket list challenge)
Step four - turn proof of concept into an open source project
That's a lot of words and got deeper than I intended and not even sure I answered the question - lol.