If you’re building Ruby web apps (Rails, Sinatra, Padrino, …) and you haven’t tried out Heroku, please do so. Immediately. You can run on the base package, which is more than adequate for a toy or even small business app, for free. It’s great for trying things out.
No need to dork around with Apache, Nginx, Mongrel, Passenger, etc, etc etc… Just a “git push” is all you need. Heroku has basically taken all the mundane crap that just gets in the way and lets you build