The idea isn’t new – after all, utility companies pipe power into your home as a service, so you don’t need your own mill wheel. If you want a car, you don’t need to own one but you can rent it from Zipcar. If you want music you rent it from Spotify, movies from Netflix. And ever since Salesforce took on Oracle the as-a-service model has become ever-present in the tech world. Amazon’s Web Services is on target for $16 billion in sales this year, while IBM leads in the hosted private cloud market.