Don't forget about Caché Intersystems, who provide a "modern object-oriented" MUMPS implementation. Complete with SQL emulation and a web template language that's almost a direct lift of ColdFusion(down to needing Dreamweaver to edit files stored inside the DB).
I interact with another team almost daily that has to support that. They do their job pretty well, but I really wished we simply had something like MongoDB to store some data in for a recent, rather trivial, project.
