tangor - 3:11 am on Aug 24, 2010 (gmt 0)
The obvious problem with live chat is moderation (or lack of it) and access (one on one is not quite as exposed as one to many, many to many). Depends on the type of chat, age of the users, and the location (countries). There are many forum softwares that are available, some in Perl, some in PHP, etc. Most can be folded into exisiting websites and skinned appropriately.