There are different ways to look at the economy; neo-classical economics, with its emphasis on equilibrium and maximization, is the dominant way. If one were to employ different paradigms, the mathematical tools used in current economic modelling are usually insufficient. Computational economics, for example, agent-based modeling makes it possible to model everything that is expressible in words. While the employment of computational methods gives us the ability to model new paradigms it gives us new challenges. This introductory talk will give you an insight of how the three tools abcEconomics, abcBalancesheets and abcContracts allow you to formulate your vision of the economy. Those visions could span from a financial balance-sheet centric view of the economy that is useful to understand the last and future financial crises, to the modeling of a real supply chain.