ASCII Tetris in Scheme!
Just load the code file and run (play-game). To move or quit, type j, k, l, i, d, or q, and hit enter. That's all there is!
Try it online here (hit the play button near the top-middle of the screen, then follow the instructions above).
This was my last-morning-at-Hacker-School project.
Hacker Schoolers: I will miss you all!