I hate math! But maybe if I had something like this when I went to high school, I’d appreciate the subject a little bit more. What is this exactly? Portal? On a calculator? Basically, someone took the concept of the original Portal and made it playable on Texas Instruments calculators. The result is a game called “Portal Prelude,” a two-dimensional sidescrolling platformer that has 38 test chambers. Not only does this look absolutely amazing, but it’s also available for free.