Another +1 for redbean. Haven't tried v4 with the namespace support yet, and I have a feeling I will not like it as much as earlier releases, but will probably end up needing to use it on newer projects.

The dev mode approach of 'just do stuff and I'll modify the tables' has scared off many people I've showed it to, but I love the approach - sort of a moderate 'nosql' approach without giving up structured tables for more complex queries later.