Is there a cloud service provider that allows complete usage-based payment? Where you don't select how much storage/computing/bandwith you need when you select your plan but at the end of the month you have to pay for whatever you used.
Maybe my website only needs a few Mb/s of data transfer, but if a video suddenly goes viral, the cloud provider can automatically increase the bandwith to my website. And at the end of the month I only have to pay for whatever data upload/download I used. (and similar for cpu cycles, data storage and memory use)