Meebo is a web based IM service which connects to AIM,ICQ,YAHOO and MSN messenger and IM people at the same time.I tried there service it was good.This service is usefull for those people who r working in corporates where IM services are blocked;U just need a browser.It uses AJAX so its faster..But i’m not sure abt the security,it shows password encrypting when signing in.

For those who have used Windows Live,Gmail web based IM..its way much better than that..its fast,kewl and carry the provides the same interface as the IM provider..less confusing for the user.