Slim?

So... I bet this has been brought up before, but I am just curious. Given the ability to see our friends logged into the grid through the webpage, would it be possible to rig something akin to an IM system so we can chat with people logged into the grid without having to fire up the whole SL client?

I could see where it could be code dependant, I'm just curious if it's even possible.

I remember reading there are some applications that allow this. I sadly forget the names. I myself sometimes converse out of game using email. There is a slight lag but it's actually not too bad. However the person in game must IM you first, and you have to have 'send offline IMs to email' checked in your preferences.