Can anyone suggest a software tool (preferably under Windows XP or later) that would launch an application or script in response to a phone call being received on a landline phone line connected to a data modem on the same PC? or, better, in response to a sequence of touch-tones being played over such a phone line. This would allow, for example, using the telephone to manipulate firewall settings so as to create another layer of security in connection with remote internet access to that computer.

I seem to recall seeing tools to do this sort of thing in the days before broadband internet access, when there was more attention to various tips and tricks for the dial-up modem, but a few attempts at Google hasn't turned anything up.