You go, Tae Bo, Meebo!
Wow, what a terrible title, eh? My 8th grade journalistm teacher would frown upon such terrible usage of alliteration. Anyways... those who have the pleasure of working with me directly, know that I love Meebo's service. Being able to aggregate all of your various IM accounts into one web interface is pretty awesome. Many organizations have explicit policies regarding usage of P2P and instant messenger applications. While it is a matter of symantics, it allows you to do your personal or work related IM activity on a computer that you wouldn't want to install an IM client on. The Meebo Repeater software package can allow you to do IM'ing from places where meebo and other services are blocked at the firewall or internal proxy server. Doing IM from random web cafe locations can be a bit safer using Meebo instead of using the IM software loaded on the systems on site. I had used Trillian, GAIM and Pidgin extensively in the past, so I didn't know what to expect. The fact that meebo uses a heavily modified GAIM as part of their infrastructure lends credibility to how awesome their service is.
I don't use their add-on toys, Meebo rooms or chatlog features, but I can see that many people would find that interesting and/or useful. If I am at a location in which I want to get on the Internet, but don't have my laptop with me, my method of choice is to boot up a system with Knoppix or Damn Small Linux, then use Firefox to get to Meebo. DSL linux will actually fit on a thumb drive as well, so you can carry a clean operating environment on you keychain.