Semiconductor spins are among the leading candidates for scalable quantum computing because they are fast and small, potentially allowing for the integration of billions of qubits, while possibly even taking advantage of already existing semiconductor scaling techology. In this colloquium, I will present our recent experiments studying the fundamental physics of such spins. Lower temperatures and control of the direction of the applied magnetic field have made it possible to observe the hyperfine spin relaxation mechanism and to obtain spin relaxation times as long as 57s -- a new record for a spin in a nanostructure.