Bill has another thread with an ICM image, and Andre asked what ICM is. Rather than hijack that thread, I decided to start a new one.
I've played with ICM a little bit for several years. I've seen lots of truly beautiful ICM images, but most of my efforts have been flops. IMHO, there are two difficult parts. One is deciding what blur adds to the image you want. The second is actually making it work: estimating how much movement and how fast to do it, and coordinating that with shutter speed.
To illustrate the first point, here is one of the very few of mine that I didn't discard right away. It's a photo of the water lily pond in front of the Clark Art Institute in Williamstown MA. I threw out almost everything I took that day. I eventually decided that I needed to preserve focus on the horizonal axis for the sake of the vertical stems, so I tried to use only vertical motion, pivoting on a ballhead. Most of the images I captured in that manner failed for one reason or another.
On an entirely different topic, this is one of the few images that I have printed on matte paper, for obvious reasons.