YouTube is arguably one of the most addictive sites on the internet – and not just because it’s the official home of the internet’s cat videos. Part of YouTube’s mass appeal is that it doesn’t discriminate: there’s a Youtube channel for everything. You can use it to learn to cook, take part in exercise classes, learn from the world’s brightest minds, gossip about people you know (and people you don’t), and ironically, figure out how to be more productive. These…