Granger causality has become a very powerful technique to reveal networks structures from a give set of time series data. In recent years, we have developed many new techniques  to apply the Granger causality to neuroscience and molecular biological data.
Figure: Granger causality and its extensions, from 
 Frontiers in Computational and Systems Biology; Feng J.F., W.J. Fu, and F.Z Sun(eds.), Springer-Verlag,2010
Figure: An application of Granger causality to resting state fMRI data gives us the brain structures (work in progress).