It's a neap tide on the Dee estuary, and as the wind picks up the exceptionally dry sand starts to move. In time-lapse, it almost seems to flow, like ripples on a pond. This was shot at Red Rocks, Hoylake, on 8th April 2014.
Produced using Magic Lantern ETTR (4th April nightly build) and in camera deflicker, on a Canon 5DmkII, through a Canon CN-E 35mm T1.5 lens and Tiffen IRND 1.8 filter. It's a shot every 12 sec at T16 with shutter and ISO controlled by Magic Lantern. It ramped the exposure by about 10 stops. No post deflicker was used, just a gain ramp of -2 stops over the second half of the shot, to stop it being unrealistically light at the end.