I found a site called Open Source Rails. It is a listing of sites that are written in Rails. I will look at it in more detail later.
It might be a good way to see how some high-profile Rails apps test stuff. I think I might be able to see how certain things are done and tested in Rails, sort of like a Rails cookbook.
Image from the Rheinau Psalter, a 13th century manuscript housed at Central Library of Zurich. Image from e-Codices. This image is assumed to be allowed under Fair Use.