The Muffin is a lie.
Screw learning about inverse trigonometric functions! Now you can play Portal in class, looking like you're hard at work! A video was posted earlier about the game. The via link is to a download of the game. Note that you need TI Connect, and a TI-83 or 84 Plus calculator. Open the ReadMe files to see how to install it, and have fun for once in math class tomorrow!