No database

Every once in a while (especially with scripting languages), I come across the intriguing phrase "no database required". Often as a feature (example).

It sounds as silly as "no file system required, prefer raw disk blocks!" to me... What's next - no data structures required? no programming language required?

I s'pose the cause of this is the deployment hell involved in using any of the mainstream databases. Sensible objection, but wrong conclusion.