There is a very interesting storage system designed for Apple's Newton OS that was buried when Steve Jobs killed the Newton: http://en.wikipedia.org/wiki/Apple_

There is a very interesting storage system designed for Apple's Newton OS that was buried when Steve Jobs killed the Newton: http://en.wikipedia.org/wiki/Apple_Newton#Data_storage http://en.wikipedia.org/wiki/Apple_Newton#Data_storage In short, it's a modular object storage with a rich set of indexing and quering mechanisms, tailor-made for NewtonScript. It isn't some quirky experiment that never got out of CS academia's ivory tower - it had real-world applications and a noticeable installed base. EDIT: changed the link