Yes photons have mass. Nothing can ever reach the speed of light because as it's mass aproaches infinite the force to accelerate it also becomes infinite. Right? So as you aproach the speed of light your rest mass is no longer at rest so you get "heavier". At the speed of light simply multiply rest mass by infinite and you get your actual mass. Keep in mind that this is all relative so you'd still think you were at rest but any outside observer would see you as an infinite mass. Now aply this to light which has zero rest mass but since it always travels at lightspeed you multiply by infinite. Zero times infinite is one. ( this is since one over zero is infinite ). So now a zero mass is something. ( at the speed of light ). Photons have zero mass at rest but at the speed of light have some mass. Besides all that.......E=Mc^2. To say a photon has no mass is to say it has no energy. would a photon be a photon without energy?