Demoniac is a tool for exploring and animating graphics effects.

Demoniac is based on effects. An effect is a piece of software that computes
an image, given some options. Demoniac allows you to create one or more
instance. An instance is just a specific effect with values of it's options.
An option (or a parameter) is some value that influence an effect. It can
change during time. The way of producing animation in Demoniac is keyframing.
Keyframing consists in making one or more value/time pairs and interpolating
the value between the keys.

WWW: http://www.calodox.org/demoniac/