For Money app, I ran into a problem with the charts drawing ugly x-axis when the datapoints were too close together. I didn't want to reproduce the problem locally because it would involve a lot of data entry. So I set out to look for some sensible solutions.
The first thing I did was look through Rail's default database Rake tasks. The most promising of these was 'db:schema:dump', but unfortunately, this only dumped the database schema structure without dumping the actual rows. Then I remembered hearing Adam Wiggins talk about Heroku a few weeks back. I remember being impressed by his product pitch. But more importantly, I remember Heroku had this feature of uploading your existing data to be imported into their database. So I looked through Wiggin's github repo, and sure enough, yaml_db was there.
The README is pretty self-explanatory, and it worked as advertised. I remember Wiggins mentioning that Heroku had problems with loading yaml files on the order of gigabytes, but this isn't really won't be an issue for me for a while.
I know that at Coupa, we have our own in-house solution for cloning production instances for testing purposes. There is a Capistrano task for it, and it has extra logic to reset all passwords and overwrite user emails with generated ones. I'll look into that when I have a need for it.