I have never seen anything like that in my life. I had assumed they must be some kind of purposeful artwork or something—and then I saw that the author had reproduced the same effect for himself. It was like being introduced to a minor law of nature that I had never happened to meet before.
This page demonstrates a true hacker ethic: playing with interesting phenomena to find out how they work. Aren't we lucky that you don't need electronics to hack!
I far prefer this article to the one that's on Reddit's front page ( http://unicurvedmirror.blogspot.com/2011/01/i-have-been-gett... ), if only because it doesn't make the ridiculous -50 degrees (celsius) claim. I'm in Victoria, and it's currently 2 degrees, which is about the coldest it's been in a month.
Fascinating! He quotes a description of something I've seen before in NW Washington, but could never explain:
>". . . ice-excrescences of soft, brilliant, asbestine appearance, and uncommonly delicate to the touch. . . ."
Saw it on a hike, growing from logs. Very soft to the touch. I would compare it to cotton candy, but the strands in cotton candy are more heterogeneous and less organized.
I wonder if a similar effect is responsible for the little stalagmites that occasionally grow in my ice cube tray. (Yes, stalagmites. No, there is no moisture source above the tray.)
Strange things in nature. I remember a natural' hologram produced on a car hood that had been waxed with a gritty cloth, when an ice sheet formed on the hood.
I suspect using a square steel tube would work better because it gives the pipe a very tiny bit of give relative to a round tube. It would allow a smaller hole and faster extrusion without cracking.