I just did remote support with windows live messenger 3 weeks ago. Not sure if we are talking about the same thing here... I also use teamviewer to support my clients' clients. Very effective and free for personal/non-commercial use.
Yes, live messenger, but I have since several years more and more problems, "Remote connection could not be established"
I have also the team viewer, but my usage is commercial.
I do not like to have some days in the future a letter from a lawyer about this.
And now in the economic crisis with declining AdSense revenues, it's hard to effort some hundred EUR.