|more useful options
XML available for chatterbox and other usersby vroom (His Eminence)
|on Jun 01, 2000 at 21:24 UTC
If you want to roll your own chat clients now there's XML you can easily get your hands on to get all the information you need.
As for the other two I wouldn't suggest grabbing the regular messages more often than once every 10 seconds and private messages more than once every minute.