Hidden Tracks

I was experimenting in Illustrator, trying to create a good image for the CD that Ed and I are producing for our partner work and I created this completely by accident.
After creating the cover and thinking how well the lines go with each other (I should be using this for the 'what is a line brief'!) and how they disguise the words 'hidden tracks' I decided to experiment more with lines for the back of the CD and created a really crazy optical illusion.

The first is a screenshot direct from illustrator (I do a lot of digital work and I don't think I post enough images of the process) and the second is cropped image showing just the cover and back in diffirent colours.