No.6 (Should be non specific) Simple waterfall Create an image map of blueish-greenish streaks. In photoshopCS2 you can do it by picking two colors and using the render fibers filter,(Looks really great if you use plastic wrap after, with high detail and low smoothness) or in other programs, use noise and vertical motion blur. Make sure the image has no seam when joining top and bottom. (In photoshop, use the offset filter, and the healing brush, or the cloning tool). In a video editing program, make a 1 second loop of this image rolling vertically (downwards). Apply this video loop as a texture to a simple arcing piece of geometry, (your waterfall) make it somewhat transparent (about 40%) snd give it a small, strong highlight. (You can even put the video in the bump channel). Add some particle steam or volumetric clouds churning at the bottom, and you've got a lovely animated waterfall, that will render faster than all particles, or an animated procedural material.