Actually TouchLight is my work, not Stewart Tansley's.  In this video, Stewart is interviewing me (Andy Wilson) who's showing the demo in the video.

TouchLight will be presented in October at the International Conference on Multimodal Interfaces (ICMI 2004).  A copy of the paper can be found at

http://research.microsoft.com/~awilson/papers/icmi2004touchlight.pdf">http://research.microsoft.com/~awilson/papers/icmi 2004 touchlight.pdf

I'm very appreciative of all your comments!

Andy Wilson