I am at Paideia Computing Corporation. We are working on conversational interfaces for NPCs and other online media (advertising, education).

We have some videos available here. There's also a preview of our current demo, the dancing parrot here.

Most interesting from a research point of view is our use of the Discrete Event Calculus to control the characters. There's a draft paper here describing the approach. I'm very interested in finding if others who might be interested in this approach!