I remember a time that IM (Instant messaging) programs were scarce. That’s right, it was hard to find a decent program for communication. The top dogs were ICQ, AIM, and MSN Messenger and they all sucked back then compared to the features available today.
I use Skype and Google Talk on a daily basis. For me, this covers every base I need, but then there’s times that people need to communicate with me and they only use a particular medium. In those cases I only use Aim or MSN Messenger.
Anyway, here’s a huge list of Instant Messenging programs that list all kinds, from desktop to web-based to network im programs.