Just thought I'd give a heads-up on this one. Here's a cool and free Windows application.
From the readme file:
 
"MiniOcean is a background generator. As its name implies, MiniOcean gives you the power to make any type of ocean scene. Based on powerful realtime  engine, it is extremely fast. You can see the results in real-time, and don’t have to waste your time rendering. Furthermore, you can have some cool post effects like Bloom, Soften, Blur, etc.in realtime!!!

Features:

- 3D Realtime Wave
- Realtime adjustment wave properties (wind speed, height, choppyness etc.)
- Camera movement
- Post render effects
- Different sky styles
- Export to single image or images sequence

This software is so easy that you won't need any tutorial. Just press all the buttons in the toolbox, slide some sliders, after that press the Play button, choose record (esc to stop recording) and you're done! All the recorded pics are in c:MiniOcean folder."

You can download it here: http://3dbud.com/stuff.htm  Don't forget to copy and paste the free serial number directly underneath the download link when you're installing the program. You can see an example of what I've done with it via this YouTube link:  http://www.youtube.com/watch?v=PlnVx1oLYwM  Have fun creating your own virtual oceans!