I haven't heard of a program that does that sort of thing, although I agree, it would be useful under certain circumstances.

Of course it would have to be updated regularly to keep track of ports, and come to think of it, most firewalls tell you which port an application is trying to access.

So I guess what you would want is a firewall that can tell you what port an application is using to try and access the net. I believe Zone Alarm does this, but don't quote me on that. You can find out for yourself here: http://www.zonelabs.com/store/content/home.jsp

Sorry this is so eradic.....I was thinking while I was typing. Never do that.