https://i.ytimg.com/vi/tojD1kzr3Ro/hqdefault.jpg

http://www.blenderhd.com/

Because the original video was too long to upload, I had to awkwardly split it up into two parts.
This video covers how to access the foam from inside Cycles, how to set up a realistic ocean shader, and a quick compositing setup at the end.

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