Shoutbox

I was wondering whether it is possible to make a script that gives MSN some of the functions that I love from Xfire.

I am quite a heavy gamer and people that try to get hold of me usually have to wait a few hours before I realise that I have a message waiting for me. When you get a message you get a toast that comes up over the top of the application (Opacity changable maybe) and then you can press a hot key that then brings up the chat screen (Again, Opacity changable) on top of the current game (So you can still play the game at the same time!!!) so that you are able to chat.

I know that this is a fairly big task, and I'm not sure if this is able to be done with the limitations of the scripting, but is there? If there is then I am sure that the script will be a big hit (About 10 friends I know that would use it straight away).