I’ve looked at the Online Status Indicator tool and I’ve noticed a few things. First of all you don’t need to ‘register’ to use it. Just point to the URL and it works anyway. Secondly if uses a small bit of VBScript to start up MSN messenger so it should be fairly easy to make clickable links from that.
codeType=application/x-oleobject id=IMessenger width=0 height=0></OBJECT>
I’ll be working on it….