I've made one like saravincent posted. It's not 'hard' per say, just a bit more tedious when it comes to cutting the fabric. You have to be precise to get the right effect. Once you figure out your repeat, cut your fabric, pin through the same spot on all your layers and cut. Flat pins are handy for that part. Once you get your fabric cut, it's no different than regular piecing. The results are pretty amazing in my opinion. The beauty of it is, you could totally transform an UGLY fabric into something really beautiful to look at! Hope you try it, I'm sure you will be pleasantly surprised how easy it is.