Rmagick - Ruby image library.

I have used the Rmagick to create the gif2led, which is used for my hardware led projects. You can find more detail at http://www.bitartist.org/2008/06/gif2led-released-and-with-my-led-egg.html

It is a very simple application, and involved some manipulations on animated gif with Rmagick. The code is simple to read if you are interested in working on animated gif in Ruby.