  Several structures have been discovered embedded in regions of recent or
ongoing star formation, which point to the importance of the interaction
between fast moving wind-blowing stars and their environment. Using
hydrodynamic simulations, we investigate the passage through the interstellar
medium of a supersonic stellar wind source, and show how it can naturally lead
to the formation of tubes, channels and swamps of globules as interfaces are
crossed. The results are in excellent agreement with observation of 30 Doradus.
