Also known as the "Goblin Shark", the Tenguzame is a rarely seen dweller of the deep. Named after the long nosed goblins of Japanese folklore, 'Tengu', and a variation of the word 'same', which means shark. Their mouths extrude from their faces in an almost grotesque fashion. Naturally gray, but sometimes found in a purplish color: [link]
They really look quite monsterous!
Cool, huh!? 8)

The video here [link] you can see a live one in action. The second half gives you a good all around look at one, just swimming naturally.

-The Tenguzame