Answer: Sega Dreamcast

The Sega Dreamcast, released in 1998 and the first of the sixth-generation video game consoles, included something right out of the box that no other video game console before it had: a modem and an existing network for online gaming.

Unlike prior consoles that either required expensive add-ons for limited modem-to-modem play (such as the Super Famicom, the Japanese release of the Super Nintendo Entertainment System) or that had no network gaming component to speak of, the Dreamcast came with a dial-up modem (with later support for Ethernet) and a network ready to link together its online-enabled games. At the peak of the Dreamcast’s popularity, there were over thirty games you could play online through the first-party SegaNet and third-party game networks like GameSpy and Dreamarena.

Although Sega ceased support for first-party online play in 2002, crafty players kept several Dreamcast games alive and kicking. As of 2013 you can still play Maximum Pool, Phantasy Star Online, Planet Ring, Quake III Arena, Sega Swirl, and Star Lancer as well as a Dreamcast port of Doom online using third-party servers.