Oh and another fascinating thing i read/heard about somewhere recently... the "speed of light" (otherwise known as "c") is the fastest thing there is.... except it's not. Light can travel at all speeds... recently it has been slowed down so much that it actually stopped. (Amazing- those Bose-Einstein condensates- imagine outrunning a beam of light!). Anyway - the fastest that ANYTHING can travel (including information) is "c". There's nothing particularly special about photons in this regard.... er.. i think.... i need to go back to university and do a physics degree.