This image can be configured in a variety of ways, for example adding or muting nature sounds, stretching the image to fit your screen resolution, playing music to accompany the image, or displaying a clock in the corner of the image.
The screensaver itself is quite pleasant, and the waterfall is animated so that you can see the water flowing and a bird or two fly by in the sky. It's nothing spectacular, but it's enjoyable in its own way.
NfsSmallWaterfall is a good alternative to Windows' default screensavers. It is both lightweight and attractive.