In order to find an explanation to the observed accelerated expansion 
of the Universe, a large number of Dark Energy models have been 
proposed in the last 20 years, ranging from simple scenarios with a 
constant equation of state to models considering a global and/or local 
interaction between Dark Energy and Dark Matter. It is then crucial to 
be able to make testable predictions for these models, especially 
regarding their effects on structure formation. N-body simulations are 
therefore a unique tool to provide such predictions and will be of 
central importance for the comparison of different competing 
theoretical scenarios with the large wealth of observational datasets 
expected in the near future (as e.g. from the DES, HETDEX or EUCLID 
surveys). I will review the main features of interacting DE models, 
and discuss the numerical methods required to include them in 
presently available N-body algorithms. I will then present the results 
of a series of N-body simulations for a wide range of different 
interacting Dark Energy scenarios and discuss the impact that Dark 
Energy interactions can have on large scale structures and on the 
properties of collapsed objects.