The Bitcoin blockchain has been referred to as a Timechain. It tracks time in an immutable way. Which is very powerful. Thought about a use case that could help offset deepfake video, which is or will become a very serious issue soon..and that is, images and video footage can be hashed and that hash stored on the Timechain serves as hard evidence that the image/video was recorded NO LATER than the Timechain time stamp. I can see a future where certified cameras are designed with video hashing built in with automatic content hashes stored on the Timechain. Where video authenticity is crucial, early customers of this tech may include CCTV and police body cam feeds, among others.