Cryptocurrency. Bitcoin and Ethereum. From those annoying pop-ups and emails with Harry and Meghan’s photo to Elon Musk's tweets. Crypto is hot and happening. But the real crypto boom is already over. Thousands of online coins that have been worth nothing since 2016 are now floating around the internet. So how do you know when a cryptocurrency will be worth something? Will we use Bitcoin to pay for our supermarket shop in the future? Will Ethereum also become the way to pay for art, NFTs aside?