As I was driving towards the Caldecott Tunnel I saw the slanting sunlight coming through these eucalyptus trees, conditions good for producing the "ray" effect. I took this out the passenger-side window; I guess the combination of motion, glare, and maybe chromatic abberation spread the rays into a spectrum for me.
Uncropped, resized. One tone curve to increase contrast. Three passes with USM filter at 88%, 0.8dia, TH=5. JPEG=7/10.