Tips for writing your own Rails engine — GIANT ROBOTS SMASHING INTO OTHER GIANT ROBOTS
http://giantrobots.thoughtbot.com/2009/4/23/tips-for-writing-your-own-rails-engine

Some very good advice from Thoughtbot on constructing Rails Engines. I've started using their [Clearance](http://github.com/thoughtbot/clearance/tree/master) engine for user authentication.

from GIANT ROBOTS SMASHING INTO OTHER GIANT ROBOTS