Ask HN: Share some insights about the economics of online storage.

Let's say you want to start a startup which is a Flickr/Dropbox alternative or any other similar service that provides online storage. What's the economics behind such business? If you are bootstrapping such business at a shoe-string budget, what is the most cost-effective and reliable way to store files? What will be the cost/GB of data and how will you go with your pricing so that the business is profitable?