Yes, you really can put on a special headset and have the electrical signals from your brain help you play a videogame. It's still early days, but there are a variety of Products designon the market and plenty of others in development.
NeuroSky's sensor tech
NIA Game ControllerFacial muscle tension, eye movement and thought all generate electrical signals. The NIA (Neural Impulse Actuator) game controller maps these signals into PC controls, allowing gamers to play PC games without using their hands. The headband reads the signals, which are then amplified, digitized and separated into different frequency bands, which are mapped to keys and mouse clicks in the NIA software through the use of NIA profiles for different games.