Our efforts over the past 20+ years on the synthesis and study of polycarbosilanes has led to the development of a precursor for SiC that is now being produced and used commercially to fabricate ceramic composites for a variety of applications, on earth, such as friction materials (brakes) for motorcycles and other land vehicles, and in space, in an emergency repair kit on the U.S. space shuttle. The basic research that led to the discovery of this precursor (a hyperbranched) polycarbosilane), as well as the applications that have resulted, will be described, along with the results of our more recent efforts to employ a novel series of cyclolinear polycarbosilanes as a source of low-k materials for integrated circuits.