This concept is a staple of special effects: laser weapons charge with a spherical glow, alien ships trail cones of green light to abduct the unwary. It's something any 3D animation software can produce, and something I personally think is a lot of fun, and probably overuse in my own works. (for gratuitous but gorgeous abuse of volumetric lighting, go see Lord of the Rings.)
So tonight I was waiting for the bus, and across the road from me was one of Seattle's everpresent orange streetlights, and beneath the streetlight was an ornamental cherry tree just beginning to open its silverpink flowers. So instead of fog to catch the streetlamp's light, there were tiny silver petals, and so I saw a cone-shape of delicate silver/orange and uneven texture. It was very windy, and the wind chased itself around the branches, and shook petals free as falling pieces of broken light. The petals shifted and seethed like the sea, snakescale flakes of light.
It occurred to me that animation technology could in no way accurately replicate this effect. I think this is a very good thing.