[Rails] [Maybe OT] One Button Deployment of Rails App

[Joe Van Dyk]

Has anyone set up a one button deployment system for their Rails app?

Say you're developing a few sites for different clients.  You add a
feature, test it, and want to deploy the application.  How do you do
that?  I'd imagine that, at the very least, the config/database.yml
file needs to be changed for the life site.  And probably some other
stuff needs to be changed when the site goes live (or gets updated).

So, how do you do it?  What's the Right(tm) way?  

I guess I'm also looking for some general admin tips.  A friend and I
are doing a couple Rails sites and I seem to be spending a lot of time
setting up Rails stuff, starting/restarting webrick, figuring out the
database situations on the testing and live servers, etc.  Any ideas?

Thanks,
Joe