An anonymous reader writes: Transcranial magnetic stimulation has been used for years to diagnose and treat neural disorders such as stroke, Alzheimer's, and depression. Soon the medical technique could be applied to virtual reality and entertainment. Neuroscientist Jeffrey Zacks writes, "it's quite likely that some kind of electromagnetic brain stimulation for entertainment will become practical in the not-too-distant future." Imagine an interactive movie where special effects are enhanced by zapping parts of the brain from outside to make the action more vivid. Before brain stimulation makes it to the masses, however, it has plenty of technical and safety hurdles to overcome.