Sky is a large sphere, ground is a plane very near the top of the sphere (inside).
Sky is textured with a solid 3d procedural texture, fractal Perlin noise.
Ground is textured with a solid 3d procedural texture, fractal Perlin turbulence.
Droplet-from-nowhere is a chain of cone frustums, generated by tweaking some code from my 
"Bezier cylinder spline" primitive from Modeler and outputting to a file.
Imagine that the droplet is hanging from a blade of grass or a twig. That was the original 
idea, at least. ;P