[ZackJ37]

While there are other document storage services, I'm not aware of any that make commitments for storing data 100+ years. For Fidelius I'm offering a 10 year notice / storage if the service ever sunsets, and I've seen similar from other companies.

The obvious concerns here are the storage media used, the DR plans for the service, and more importantly, trusting that the company will do right by you after you're gone – even if it goes under new management or bankrupts. While I always struggle to find applications for blockchain, perhaps this is a scenario where it could be useful... perhaps you could upload the encrypted data to the chain, and form a contract where the key to decrypt it is released after X years?