I go to an N-scale only site and it has a chat box. I have had a few lengthly conversations but was evaluating the rest of the site and noticed very few posts. The posts and responses that were in there had quite a bit of time in between. I hope we never have it here as we would miss out on some great discusions. Also, one could not lookup vareous topics as chats are not archived.
John heresa couple of forums that alsohave chat,quick replies to questions etc.
http://2guyzandsumtrains.com/index.php
http://tracksidemodeller.com/index.php
these are not scale specific but theres n scalers hoersetc.
Tom