I think you need to read up on Einstein's theory of relativity.
According to him, the speed of light is finite. Thus, if two objects move away from each other at the speed of light, both will perceive the other object as moving away at the speed of light. From someone observing these objects from a distance, both are moving at the speed of light (which is correct).
It's like the question, "what happens if I drive at the speed of light and turn on the headlights of my car?". The light from the car will leave you at the speed of light. They will NOT leave at the speed of light plus the speed of light. this is rather counterintuitive, but that's what the theory says! But the entire question is meaningless, because objects such as cars cannot move at the speed of light.
Check out this page:
http://www.weburbia.demon.co.uk/physics/headlights.html
Saying that the person inside the car is staying relative to the car is actually irrelevant. It does not matter whether an object is moving or the world around it - the speed of light is the same.
Now, an interesting phenomenon is entanglement. When two entangled photons move away from each other at the speed of light, they STILL react instantly to events affecting one of them. This seems to be communication at a faster-than-light speed, and has been at the heart of many raging debates in particle physics (and still is, I think).
Tormod
