Message passing (Facebook style)

Hey,

I was wondering how i could implement a message passing facility through a social networking website i am making. Instead of creating it all from the start, is there a much more simple approach i could possibly take?

I quite like the way facebook does it, how is this done?

I am ok with AJAX but would prefer something really simple not to the extent of adding emoticons etc…

How can i do this?

There is no comment control that I know of. Best bet is to build your own. Build one control and use it over again. It should not be that tough to do.

But I would stay away from MS Ajax and go with jQuery rather