I have been wondering two things. 1. Why is it that the speed of light, is regarded as some sort of holy grail that will open up everything for mankind (this is the general feeling I get when I read/watch various things on the subject). I mean from my general understanding "the speed of light" is just that. Much like the "speed of sound". 2. Is it (and if it is, how is) it possible to generate gravity without centrifugal force? I ask the second question because I've always been interested since watching many programs as a child where they would have gravity on star ships and space ships, then rooms without gravity on planets (you walk in and can drift about and then go to the door and walk away) Sorry if these are in the wrong section.