text: You just need to know the connection protocols for the service you want to connect to. \n\nYou might want to check out http://developer.aim.com/ for tools to help create your own aim client.\n\nHere is a sight that describes the Yahoo! Messenger protocol: http://www.venkydude.com/articles/yahoo.htm\n\nJust type in "messenger protocols" into a search engine for better results.