Another of those great images of sea phenomena that I like, cross (or grid) waves, which occur when two sets of waves travelling from different directions cross at an angle of 45° or more. This creates very steep short-crested waves that can be dangerous for shipping. From the European Space Agency.
Put some Channel Swimmers out there, you could have a game of Sea-Chess and get some good training in.
EDIT March 21st 2013: This post is getting a hammering from people that don’t believe this is real. Please check the comments for my update & explanation (that it is genuine and how it can be caused), and also a way for you to check the photo for yourself, if you believe the European Space Agency (and I) are lying to you.