I recently climbed Mount Jefferson with a couple friends (10/24/10) and was amazed by all the rime ice formations. I didn't completely understand how the feathery looking features were formed, but the MWOBS web site had a good article describing the process. One of the aspects I found interesting is the counterintuitive orientation in which they're formed. Apparently they form in the direction the wind is blowing from. In other words, the fragile tips of the feathers point in the direction they were formed. The lighting was a little flat that day so I had to do a little post processing to tease out the intricate details of mother natures art work.