The Galaxy S II has at least two custom live wallpapers, beach and windmill, and XDA pulled them so we can run them on other Android phones.
Watch this video
to see them running on a Nexus S.
I've uploaded the Windmill wallpaper APK below.
You can grab the Beach wallpaper APK here
(file size too high to upload directly).
Screenshots (they change with time of day):
And here is the XDA link