One of the more interesting examples of cartridges with built-in modems was the GameLine for the atari 2600 https://en.wikipedia.org/wiki/GameLine https://en.wi

One of the more interesting examples of cartridges with built-in modems was the GameLine for the atari 2600 https://en.wikipedia.org/wiki/GameLine https://en.wikipedia.org/wiki/GameLine It would fail but they created a new company called Quantum Computer Services which would come to be known as America Online. http://www.atarimania.com/game-atari-2600-vcs-gameline-master-module_20315.html http://www.atarimania.com/game-atari-2600-vcs-gameline-maste...