These three lines should be removed:

* We want to keep the `database.yml` in there, I'm pretty sure. Or else we should make a rake task for generating a sane default and documentation in the README about it. And make the default rake task check for the file and give guidance when missing, so that someone can recover from not having one as easily as possible.
* `.DS_Store` is specific to your operating system, not this project, so it should go into your global git ignore file.
* I think Rails relies on `/bin` being checked in for, like, `rails server` to work, etc.