Ask HN: Where in the cloud is best to host node.js?

I'm working on a new system who's server component will be using node.js. Like any other start-up effort I'm looking for a place to host this with zero-to-low cost initially but with the capability to scale up rapidly when necessary. I've used Google App Engine in the past for this sort of thing but as far as I know, I can't use it to run node.js. Can any of you offer suggestions or tales of your experience with cloud hosts who would be capable of hosing a system like this?