The official Web site of AOL Instant Messenger. Exchange messages with friends, family, and colleagues online.

Allows you to instant message with anyone on the Yahoo server. Tells you when you get mail, and gives stock quotes.

Internet Messaging service that provides instant contact with the greatest number of Internet users and works with your favorite communication tools.

Official site for the ICQ instant-messaging and chat software.

Provider of custom Jabber client/server solutions for corporations. Major funder of the Jabber.org project and author of the JabberIM windows client.