Rails standalone App

How can I get my app into a standalone like Vision (http://
vision.shopify.com/). Basically it is a Rails APP that can be
launched from the desktop. It opens up a terminal like window and
automatically launches the App in a browser. Any ideas?

I am able to follow the tutorial and get myapp_darwin...but it has no
instructions on how to run it

Anyone has already tested this solution? What about
http://blog.zenspider.com/archives/zenobfuscate/ or parsTree?