'Brainwave' Cap

Although this isn't really all that new of an idea, the BBC reports 'Brainwave' cap controls computer. The biggest thing is that it's non-invasive, while many current BMI devices involve implanting electrodes in the brain.

"Brain activity produces electrical signals that can be read by electrodes. Complex algorithms then translate those signals into instructions to direct the computer."

This passage has me wondering what kind of hardware is required to do this processing and how much electrical power the thing consumes, with regards to the possible portability of the system.