Where is blockchain most needed?

Blockchain is fascinating! And not because of cryptocurrencies, but the technology is great. Just think about it:  you can write to blockchain anything you want, not just coins and transactions. It all began with decentralized peer to peer electronic cash system but it's now more than that. It can serve as universal digital identity system, voting system, you can use it in medical care, etc.

I'm currently a student and I'm trying to find master thesis theme related to blockchain because I want to contribute to creating new applications for it.

What do you think, where is blockchain most needed today??