This has been discussed in a number of threads and in FAQs. I was wondering what constituted a rest frame as nothing in the universe is at rest, if you work the figures out we are moving at around 2.5% c. In another thread I found out that at rest simply meant not accelerating. This means that despite what has been said before photons moving at c are the only things permanently at rest, they cannot go faster than c, they always move at c and can only decelerate which means their frame of reference can only go in one direction. All other things have the choice of going faster or slower and so moving their frame of reference in either direction, this is obviously why c is so important in relativity, it provides a floor that all else is built on. Therefore photons are not moving at c from our frame of reference but we are moving at c from a photons frame of reference. So by going faster we are actually slowing down from a photons frame of reference, so is everything we think we know back to front.