Shoutbox

Hey,
I was wondering if anyone knew of a light version of a messenger program that supports msn contacts.
I have been taking my laptop to uni every now and then and have had times when i need to contact people through msn. We have a web quota at uni so i dont want something with display pictures, many graphics etc just a basic one. I had already thought a webmessenger but that refreshes or reloads so often that it cant be doing any good to my quota.
Can anyone recommend any programs to help me with this?
Thanks everyone.