I've found that Photoshop 6's built in Lens Flare effects work very well. Here's a pic of my 88 200SX SE V6 at night, I used photoshops lighting effects to embellish the foglights, by selecting Filter->Render->Lens Flare. Then you just put the crosshairs in the center of the light source, select the effect and magnitude. It's fun to play around with, and looks very real.
