The document provides an overview of blockchain use cases. It begins with remembering the key components of blockchain like blocks, miners, proof of work, and distributed ledgers. It then discusses public versus private blockchains and how private blockchains allow for control over participants. Several specific use cases are outlined, including smart contracts, proof of existence services, digital notarization of photos/videos, digital weddings, lottery systems, alarm clock apps, and banking operating systems. It is suggested that 2017 will be a year when more blockchain proofs of concept and pilots move into limited production and early adoption.