At the frontier between immunology and neuroscience, microglia, the enigmatic macrophages of the brain, have generated, in recent years, increasing interest. In response to even minor pathological changes in the brain, these extremely versatile glial cells occasionally enter in an over-activating state and produce pro-inflammatory cytokines and free radicals, thereby contributing directly to neuroinflammation and various brain disorders. This review provides an analysis of the latest developments in the microglia field, considering the important new research that illustrate their involvement in brain related diseases.