Koolim Web Messenger
Web Messengers that allow you to connect to Instant Messenger networks are becoming extremely popular because they make it possible to connect to those networks and chat with your buddies and contacts from computers where it is not possible to install Instant Messenger software.
Meebo was one of the first Web Messengers that I wrote about and Koolim is a comparable service which has the advantage that it is not that popular yet (update Meebo has been bought by Google and is no longer offering its services).
Popular web services like Meebo get blocked from school, university and work networks quite frequently and it is always nice to have an ace - Koolim - in your sleeve. Koolim should work even if the computer you are working with is protected by a firewall.
Koolim supports the major Instant Messenger networks: AIM, MSN, Yahoo, Google Talk and ICQ plus several lesser known networks such as Jabber, X-Fire and Gadu-Gadu.
Every user has the option to either log into any of the IM networks by entering his username and password or by signing up to Koolim and handling matters from the inside.
Update: Koolim is still around on the Internet and you still have options to sign in on any of the supported services right away from the home page of the service, or by creating a Koolim account first and managing things from the inside instead. There is also an option to install it as a Firefox sidebar in the web browser if that is preferred.
The services supported right now are: AIM, MSN, Yahoo!, Google Talk, ICQ, Gadu-Gadu and Xfire. What's interesting is that you can sign into multiple services at the same time.
Update 2: Koolim has been discontinued. It is no longer available, and when you try to access the site, you will receive a warning message. An alternative is Plus.im.Advertisement