An anonymous reader writes "A calculator enthusiast has managed to allow TI-83 Plus and TI-84 Plus graphing calculators to connect to the Internet with the help of an Arduino board. It is called Global CALCnet 2.2 and there is already a chat program demonstrating it. Multi-player games for gCn such as a Scorched-Earth clone are currently in the works. Maybe in the near future we will be playing some variant of Ztetris against our friends on the other side of the world?"
Somebody also took the time to port Doom to a TI-Nspire calculator
. A YouTube video demonstration is available