Hello,
i do not know if my input really fits your question, but we at fettundrosig are using RB to develop all kinds of small and mid-sized web based applications for special needs.
RB just lets you forget about the database when developing your business models and at the end you have a very neat and tidy database schema. E.g. we use some tools to draw a nice diagram of the models and so on. I could never do this because my naming schemas tend to get very esoteric.
As i myself am limited to PHP knowledge i feel that the RB built database schema and a well written API documentation would empower us to, at some point, choose to redo the product from scratch with a new team or language/database engine or decide to bring to a public market whenever we feeld that our client and we use it ourselfs and i could be of use.
Nevertheless i support the question after marketed products, but also i would like to know if there are already more generic things out there like outliner, rbac, user-management which could be stagged up to a application building tool standing upon RB?!
Cheers,
Stephan