We've actually tried doing this in IRC chat rooms about a year ago. It seemed to confuse and annoy people as Hal would generate an answer for every single line typed. I'm sure it would have been better if Hal only chose to respond to some of the sentences. We are planning on adding different chat mediums to Hal in the future (ICQ, Yahoo, MSN, etc...) and we could probably add chat room support also. We probably won't start work on this until 3-4 months from now.
Robert Medeksza