Not far from reality, indeed. Every time you have some molecule with a free electron, you can perform Electron Spin Resonance on it. You take a small amount of the molecule, put in a strong magnectic field, and with microwave you could drive the transition between the down and up state (parallel and antiparallel to the magnetic field). However, with a conventional spectrometer you can't control a single spin, because its signal would be tremendosly low, you would need at least ~10^13 molecules (maybe even less nowadays). If you want to use a single molecule, you need to connect to some kind of nanofabricated structure, in order to control and read it out. It's feasible, many works showed that, but very very difficult to engineer. You could spend most of your phd trying that (a pretty common tale in the field).