I haven't seen a plugin for this and a quick search doesn't show me an easy way to do it.
If anyone else knows how to check email using VBS maybe they can post a link or a short example. I would like to make this kind of a plugin.
I suspect that CDO or CDONT might be the Objects I need. I do see that CDO can be used to send email, but I don't find any functions to check for new headers.