Not quite that but I love http://guides.rubyonrails.org/

There's this good blog that shows example apps and occasionally has articles about best practice for Ruby on Rails. It is, however, 2 years old but should be close enough for learning Rails 2.3. http://originblog.wordpress.com

EDIT: check out this StackOverflow post too - http://stackoverflow.com/questions/193632/where-can-i-find-g...

For Django look at open source apps. Registration is a good one to start.

There are enough high quality apps to give you an idea of best practices.

For rails, check out http://www.railstutorial.org.

opensourcerails.com has quite a few open source ones