1. Create a new 500 x 500 pixel document with a resolution of 100 and name it Light Ray. Press D and fill the document (with Black). Then create a new layer. Then select the Lasso Tool and draw any shape you want. Now fill the selection with black.

2. Next apply a noise filter with settings [Amount: 400%, Distribution: Gaussian, and 'Monochromatic' checked]. Now deselect the selection.

3. Now apply a radial blur with settings [Amount: 90-100, Blur Method: Zoom, Quality: Good]. Do this filter three times (x3) in total.

4. Next, copy the layer with the radial blur in it. With the new copied layer selected, apply a twirl filter with settings [Angle: 100°]. Now you can add color to the image by, creating a new layer and filling it with a color of your choice. Then set that layers blending mode to 'Color'. Below I fiddled around a bit, copied the twirled layer again, changed blending mode and erased parts to give the depthy look. It's a neat effect, have fun.