This was a project for my mother-in-law. I started out by looking at a bunch of ripple patterns, but was unable to find anything I liked. Most of the ones I saw were really ornate, and we had picked out this beautiful boucle yarn that didn't need a fancy stitch. I ended up just making up my own pattern as I went and really liked the way it turned out.
I am perfectionist when it comes to my crocheting, which can mean a LOT of stitches taken out :) What I found about working with the boucle yarn is that it is much more forgiving of accidents. I ended up leaving a lot of mistakes in there because the boucle yarn made them invisible. If you have never worked with these fancy yarns before (and are maybe a bit scared by them) give them a try! They take some getting used to - but are fun once you get going.
I have tried to type the pattern up for you - however I am inexperienced as a pattern writer - so if you give it a try and find problems, or have questions - feel free to leave a comment here and let me know!
The finished size was about 52" x 70" and I used a bit more than 2 Skeins of Sensations Rainbow Boucle Patterns Yarn - The Skeins are 11 oz each - I would say I used less than 30 oz of the yarn.
The pattern is a PDF file - you can download it here
And if the download is giving you trouble - here is the jpeg. Just right click the image and select "save image as"