So, I see no reason why this wouldn't be possible. I have a Linux server (a Raspberry Pi to be exact) connected via Ethernet to a broadband ISP. I want to be able to dial a number, have it go through the normal telephone network, onto the Internet via a VoIP provider (I know you can call a Skype user from a landline), to my Raspberry Pi, and then have the Pi connect me to the Internet. I've found guides on making your own ISP, but they all involve a dedicated phone line on the server end. Is there a way to do this with no modem on the server end? I live in an area with a lot of people still on dialup, and if I pull this off I could make some extra money. Thanks!