Which PaaS to choose?

[socialistkoala]

I´m currently developing a new project with Ruby on Rails and thus looking for a good PaaS (Platform as a Service) host. I`ve tried heroku and found it to be pretty easy to deploy and get going. but if you take a look at their prices you might get a shock.

Is there a good alternative? Or should I just learn to set up the necassary stuff on a VPS myself?