These seemingly "big" games written in a handful of lines of code always make me feel very, very stupid. I know if I made this, I could easily imagine writing 50,000 lines.
How do people do this? How do their minds work?
Take a look at the code, it's not THAT hard when you have the right tools (language, libraries, knowledge...) though it's quite awesome nonetheless.
IMHO the game actually shows how powerful Python + Pyglet (OpenGL actually) are.
Wanna get your mind blown even harder? Check some 4kb demos[1]... and that's binary size! No JVM/Python runtime supporting it.
[1] http://www.youtube.com/results?search_query=4kb+demo&pag...
I still remember how I was blown away when seeing .kkrieger[1][2] for the first time, introducing me to the potential of procedural assets in games.
[1] http://en.wikipedia.org/wiki/.kkrieger [2] http://www.youtube.com/watch?v=2NBG-sKFaB0
It's in Farbrausch's GitHub with many more demos/demotools https://github.com/farbrausch/fr_public