The NES Modem
A weird little footnote of NES history: In September of 1991 the Minnesota State Lottery actually developed a plan to allow NES owners to play the state lottery online using a modem. The modem would attach to a port in the bottom of the NES unit. Users would be provided with a security code which was intended to prevent other people from using their accounts. The security code was also intended to prevent anyone under 18 from playing the lottery.
Players could pick their own numbers, allow the game to pick numbers, or let the lottery computer pick their numbers. The system was also supposed to provide lottery news and even featured mini interactive versions of the "Instant Win" games. The outcome for these games however, was still predetermined.
In October of 1991, the project was scrapped due to political pressure. It did get far enough to produce a working game and mockups of the modem.
For pictures and more information check out the link below.
Link (via NES Kingdom)