Phone Recorder W7 is an application that allows you to join and record an ongoing telephone conversation. It runs under either 64-bit or 32-bit Windows 7.

Phone Recorder doesn´t have much of a user interface -- just two buttons:
"Start recording/Stop recording" and "Exit". When you click on "Start recording", Phone Recorder will join an ongoing phone conversation on the same line as that of the modem, and the button label will change to "Stop recording". The conversation is stored as a .wav file in the same folder as the Phone Recorder executable (.exe) file.

To run Phone Recorder, you need to have a dial-up modem that has voice capability installed on your computer. Phone Recorder uses only the voice feature of the modem -- there´s no need to "dial-up" anywhere. Be sure to tell the other party or parties on the line that you are recording the conversation if it is legally required to do so.

Recommended Modem
The Rosewill RNX-56USB modem is the only one I can personally vouch for right now to use with Phone Recorder. The drivers included in this kit are unpacked versions of the drivers for Windows 7 that I downloaded from Rosewill´s website. I´ve been told that the Zoom 3095 will also work for Phone Recorder, but as far as I can tell, it´s exactly the same hardware as the Rosewill, and the Rosewill is about half the price.