Made a program yesterday that makes really trippy spirals.  It's written in python.

http://www.newgrounds.com/dump/item/ad620c6b66880bcf20635093ef7c2f75

(dump link)

Depends on: python 2.7, pygame

python is available for windows here: http://www.python.org/getit/

pygame is available here: http://www.pygame.org/install.html

Please note, if you have linux or a mac, you probably already have python.

A screenshot (kinda) is available in my images section.