Originally Posted By: mlord
without having to also trigger the harsher onboard flash.

I've found that a piece of translucent scotch tape works great for taking the edge off. In a pinch, I've also used a kleenex draped over the flash. My current camera (Nikon D80) allows me to control the brightness of the onboard flash. I usually have it set a couple of stops below full power, which takes the edge off very nicely.