Bernardo points to a link from Zeddy Iskandar, a developer evangelist in Indonesia who used system.speech to control a robot.

Reminds me of the work of J. Norberto Pires, from the University of Coimbra in Portugal, who has a bunch of videos here:

http://robotics.dem.uc.pt/norberto/nova/videos/

and on his homepage: http://robotics.dem.uc.pt/norberto/