I found some great 1920x1080 backgrounds but none are animated

[Onceler]

I was wondering if any of you knew of backgrounds that are animated(like a stream with water flowing or clouds moving) for free, they will be used for backgrounds for my girl's fantasy video(green screen).
All my searches on Google reveal only static pics I found 1 that was a gif but alas it was static. Something steampunk(I hope I applied the correct term) would be awesome.
Thanks

 

[Annisman*]

Check out windows 7 Dreamscene.