How can I safely make sparks for a film shoot?

I'm looking for a safe way to generate a lot of sparks for a film. In the shot the character is connecting a large power source to an electronic device, like a computer. When he does it I really want the thing to light up with sparks. The only ways that I can think to do this don't seem very safe. I can shoot the sparks separately and composite them in afterwards.

I've considered doing the whole thing as a computer-generated special effect, but I'm sure that it will look fake.