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The simple discretization and flexibility of the real space grids makes them an ideal framework to implement, develop and test new ideas. Of course, an additional ingredient is required. Modern electronic structure codes are quite complex, this means that researchers seldomly can write code from the scratch, instead they need to resort to existing codes to implement their developments.  From the many codes available, in our experience the real-space code Octopus~\cite{Marques_2003,Castro_2006} provides an ideal framework for theory-development work. To illustrate this point, in this article we will explore some recent advances that have been made in computational electronic structure and that have been developed using the Octopus code as a base. We will pay special attential to the most unusual capabilities of the code, and in particular to the ones that have not been described in previous articles~\cite{Marques_2003,Castro_2006,Andrade_2012} dedicated to the code. articles~\cite{Marques_2003,Castro_2006,Andrade_2012}.  We will start with a brief description of Octopus