Facebook and Libra are focusing on Financial area. Is there any other area that blockchain can be used?? It's hard for me to imagine anything else.
There are many, many potential use cases. This is truly transformative tech that can have a big impact across society.
Picking just one important use, I'd say smart contract platforms such as ETH will be huge. It's not just an ICO platform, ETH can be used to automate many things in society. Any interaction that is rule-based and can be codified is a candidate for automation using ETH.