I have fond memories of pretending to perform algebraic equations while instead playing awesome calculator games on my couple hundred-dollar TI-83. Anyone who took a semi-advanced math class in high school or college probably shares some of these same memories.
Having said that, my time would have been a lot more enjoyable if I would have been able to play Portal instead of that "hey which urinal should I chose" game.
Today's cool thing of the day is this Portal clone, Portal Prelude, which is playalbe on the TI-83 Plus and TI-84 Plus series of graphing calculators.
If you want to play it, it's downloadable here.[Builderboy via The Daily What]