Wind Light
Wind Light is a great program in Second Life. With Wind Light you can customize and design beautiful skys and scenes. Wind Light greatly adds to the quality of photos taken in Second Life. Wind Light features a sky editor, day cycle editor, water settings, glow settings and more. Check out Wind Light in Second Life.
I have a large post with a great deal of information including images, video etc, here: Revolutionary Artistic Elemental Effects with WindLight in Second Life