Documentary trade finance - e.g cross-border trade where importers and exporters transact physical goods using letters of credit issued and endorsed by banks on both sides of the transaction. A good example is a container load of crude oil shipped from an upstream exporter in India to a refinery (importer) in the States.

Banks act as facilitators of such as transaction on import / export side, often have to interact with shipping / logistics and insurance providers to ascertain that goods have been sent in order to clear and settle payment from buyer to seller. It’s an entirely event-driven and very paper-based business with lots of complex processing logic which can very well be replaced by a smart contract, especially because each party may not trust each other a lot (eg exporter wishing to audit transactions of the importer’s bank). A blockchain works quite well for this type of problem.

Disclaimer: I do not work for Corda.