Fly through a cave, collecting the white crystals and avoiding or shooting the red ones.
Tip: always keep the nose of your ship pointed into the darkness.
Each level gets faster.
If the download doesn't run for some reason, the web applet may still work for you.

Enjoy --

you can see pictures from development at:
http://benhem.com/dumpage/Ludum
It uses Processing (Java-based), OpenGL through JOGL, and the Minim sound library for Processing. Sounds made in SFXR (woop!) and guitar bits recorded and meddled with in Audacity.