This is a rather fun diversion (IMHO, of course) that I created during a boring english class two years ago.
Dynamic lighting (Toggle-able)
High score record (per-game only)
Very small size (25KB download, 56KB executable)
Decent speed on any machine
Non-stop gameplay (Dying only detracts from your score)
Increasing difficulty after each level.
Runnable on any OpenGL capable Windows machine. Recommended 500Mhz or better for lighting effects.