Transcranial Direct Current Stimulation (tDCS) is a cheap, easy to use, and relatively safe noninvasive brain stimulation technique. It is increasingly used in several indications in psychiatry and neurology, mainly for depression, chronic pain and cognitive decline due to degenerative brain diseases. Its efficacy is probable in depression and must still be confirmed in numerous other indications. Lowcost devices for the general public are easy to find on the internet and are frequently used for non-therapeutic indications, like the improvement of video gamers' performances. A non-medical use could represent a public health hazard, due to lack of control on stimulation parameters i.e. localization, duration and intensity.