Recently a powerful example of a replicating nano-machine entered our society. In principle, it’s just a normal disease, that one attempts to model with 3 or 4 simple coupled equations with 2 important parameters: a timescale, and a replication factor (the famous R0). Then one tries to guess how changes in society change R0 and perhaps adopt some more or less strong lock-down measures. However, this virus has more “personality” than that. It behaves differently in different persons, and persons behave differently. Presumably, only a few of us infect a lot, while most do not infect so much. This assumption is supported by the observation that couples living together only infect each other with about 15 percent probability, indicating that most infected people are not really infectious. I will discuss this and other aspects of Covid-19 in the perspective of models that describe heterogeneous individuals in a society. In particular, we suggest that limiting superspreading opportunities is a cost-effective strategy to mitigate Covid-19.