speed of light

if any observer moving slower than the speed of light observes the speed of light to be a constant, does that imply that any observer moving at the speed of light observes anything moving slower than the speed of light to be moving at the speed of light, relative to itself?

i.e.:  if light could measure, would it observe a car and a comet to be moving at the same speed?

>>6
Light physically exists.  He wants to consider things from light's reference frame, what's wrong with that?