This article summarizes the studies on the secondary electrohydrodynamic (EHD) flow produced by electric corona discharge in gas. Detailed information about the development of the fully coupled EHD flow model is presented. This model takes into account the interaction between the electric field and the fluid flow field as well as the effect of the operational pressure. The theoretical model that was validated by experimental measurements was employed to analyze the dynamics of the EHD flow, the effect of EHD on corona discharge in compressed gases, and the effect of the EHD flow on the flow pattern in the ESP channel. Selected results were presented and discussed. Examples of the practical applications of the EHD flow produced by electric corona discharge were presented, including the EHD thruster, EHD gas pump, and EHD mini-pump for Martian particle analyzer.