Millions of computers are now connected together by the Internet. At a fast pace, applications are taking profit of these new capabilities, and become parallel and distributed, e.g. applets on the WWW or agent technology. As we live in a world with finite resources, an important challenge is to be able to control computations in such an environment. For instance, a user might like to suspend a computation because another one seems to be more promising. In this paper, we present a paradigm that allows the programmer to monitor and control computations, whether parallel or distributed, by mastering their resource consumption.