Spiked Ice Cube

I know there's a geek out there who can explain to me how this happens:

Thank you Jeremy!

I got this in an e-mail from him this morning:

Band geek, meet physics geek. I was meaning to write this the day I saw your blog but then life intervened. The answer to the spiked ice cube is both simple and complex; think "the path of least resistance". The ice cube in question had a thermal dynamic i.e. "warm spot" probably arranged by the blower in your freezer, this spot, just like one in a lake or ocean had formed because like temperatures well, like each other. As the majority of the cube formed this oasis of warmth was left watery; and had nowhere to go but up when surface tension around it made it the easiest direction to go. This continued until the water was used up resulting in the "spike" shape. Gravity made it fall over slightly giving it the "thorny" appearance. love your little geek bro, jkp