Online communities, like Twitter, attract thousands of users worldwide spending hours communicating with others via the Internet. Most platforms offer mechanisms that show the ‘rank’ or ‘social reputation’ users have gained within the social community the platform establishes. This chapter analyses the motivation of users to engage intensively from a social psychological perspective and follows the hypotheses that these status information function as a highly effective reward mechanism. The chapter describes the results of a survey that has been conducted with users of Twitter in order to find out how important it is for users to gain ‘followers’. The chapter outlines a theoretical construct that explains why users try to gain social reputation in different virtual worlds. For this, a typology of virtual worlds has been developed based on possible spill-over effects of social reputation that can be gained in virtual and real worlds.