When you read some introductory articles about blockchains you can often see dozens of potential applications described. However, this doesn't mean that they have been implemented in reality or have achieved a widespread success.
So, in this thread I would like you to post most successful examples of blockchain being already used by companies that have adopted it or by startups that were built around it. It would be perfect to also get an in-depth explanation of how that particular blockchain implementation works.
I've been involved in a lot of different ICO projects but I think the CS is a pretty special project for me. It is a fully upgraded blockchain system that can handle more than 1 million transactions in 1.5 seconds. And it does exactly what it says, but it does not yet have a great community to be able to thrive on their technology. that's a pity.