If you're already registered on one or more IM networks, we recommend using the free open-source software application, Pidgin, to simultaneously connect to one or even several IM accounts. Pidgin is absolutely free to use (no cost whatsoever), contains no ads in any form, is free of any spyware, has numerous third-party plug-ins available to extend its use and functionality, and is supported by a large community of users.
Links and Resources for the Pidgin software application