subversion: Subversion FAQ
Next time I forget why Subversion can't ignore a file under Subversion, check this. The answer is to not check that file in at all, but to check in a template that should be copied.
Sakuzaku: I Am Building Ruby, Rails, Subversion, Mongrel, and MySQL on Mac OS X -- Automatically (And So Can You!)
Like it says, a shell script to automatically install the perfect Ruby on Rails development environment on OS X. Useful!