Anyone Ever Heard of this ?

umm actually the product they are selling is on GM cars, anyone ever hear of Vortec(I believe thats what I am thinking about). Well what it is, is a small piece of metal that induces a cyclone effect of fuel and air. its supposed to mix the two together better and increase hp and gas milage, I have never heard any comments about people using it but hey I really never listen either. Ive seen it in ford OEM equipment magaines also but agian I have no Idea how well it works