I did a project for a bank in Luxembourg that worked like this. We were building a reporting system external to their core system and so needed some test data.

I did a project for a bank in Luxembourg that worked like this. We were building a reporting system external to their core system and so needed some test data. Because they didn't have a test system they would dump live data then edit it in Notepad to keep their customer records private. Needless to say half the problems we had were related to the Notepad editing part.