Yahoo IM might work (Score 5, Insightful)

You haven't explained the quiz-show setup. Where is the quizmaster? How are you asking questions and how are contestants answering? In a pinch: Use Yahoo Messenger for the video links and then create a Yahoo chatroom and turn on the voice-chat. Use VNC to control the remote machines; if you have three pubs, I would suggest getting another machine to handle the VNC'ing, and just leave all the others hooked up. Pub1 views Pub2 and Pub3, Pub2 views Pub1 and Pub3, Pub3 views Pub1 and Pub2 --- and they're all in the same voice-chat. Is it oh-so-hacker cool? No. Is it free and will it work? Yes.