[Dartmouth’s] Interactive Media Lab (IML) builds shrink-wrapped educational software for medical professionals and first responders. [They] have teams focusing on media production, script-level authoring, and low-level engine development.
They have released their engine, along with their object system, as open source.
Their system is pretty interesting in that they tackled a lot of problems on their own; and even after solving problems they still had to figure how to get the users to use the new code! Read about it in the write-up on CUFP 07.