1. Begin with a new file, 400×400, with a black bakground, then create a new layer in the layers palette, now take the Polygonal Lasso Tool and make something similar to the shape below. ( Click for larger view )

2. Now right click inside your shape and choose Fill, fill the shape with white, then go to Filter>Distort>Ripple and set the Amount to 999% and the Size to Large. Now should it look something like this.

3. Go to Filter>Blur>Radial Blur and set the Amount to 100, Blur Method Zoom and Quality Good. And that’s it you are done!

This is what I came up with.