I've been thinking that bank transaction reconciliation is one of the best use-cases for DLT. No need for a crypto coin, each financial institution could just hold a ledger copy. R3's Corda is being built to plug in directly to legacy SQL systems, and its founders have lots of experience in finance. If anyone is interested, I found this epicenter podcast interview really interesting:

https://youtu.be/3YTSwB5UrEI