Compliance and regulatory audits (e.g. ISO certification, SOC 2, the list goes on) seem like a candidate to me. There is typically a standard set by one organization, that has to be complied with by (multiple departments within) another organization, and verified by an auditor external to the first two organization (as well as to auditors within each of the organizations.) A database managed by any of the three players wouldn't be trusted by the others, so it seems like a candidate for multi-party distributed trust.