"Brinicle" ice finger of death

Hats off to BBC cameramen Hugh Miller and Doug Anderson for capturing this once-in-a-lifetime shot of an "Icicle Of Death" for David Attenborough's Frozen Planet nature documentary series.

As you'll find out from David's soothing voiceover, the underwater tornado - of a sort - is formed by the expanding ice above, which gives off extremely concentrated salt.

This salt, being heavier than water, goes to the bottom of the ocean, but does so in a way that somehow scares the dickens out of us.

And in case you were wondering, the footage was taken off Little Razorback Island, which is near Antarctica's Ross Archipelago. So next time you're down that way, check it out! Or, thinking about it, maybe not...