The present article gives an overview on central challenges humans face at the dawn of complex digital societies and the Internet of Things (IoT), i.e., a world completely connected to the Internet. Among the many challenges to be handled in digital societies is a growing fragmented life style leading to loss of productivity as well as moments for self-reflection. In all this, it is of tremendous importance to understand the impact of digital worlds on our brains and psyches and to reveal possible unintended side-effects of technology use. Does human nature change due to constant interactions with virtual realities? In this context, we also face the challenge to design digital worlds according to our mammalian-emotional heritage deeply anchored in subcortical areas of the human brain. Here, we refer to emotional needs as carved out by Panksepp’s Affective Neuroscience Theory and how they can or cannot be fulfilled in digital worlds. Aside from a review of several key studies dealing with the raised challenges, some first solutions to successfully meet the mentioned problems are provided to achieve sustainable and healthy digital worlds, with whom humans can interact carefree on a daily basis.