MEG Scanners Are Mega Powerful -

While other types of brain scans detail the geography of the brain or detect blood flow, the MEG scanners track the magnetic signals that neurons throw off as they communicate. "You can look at how the networks of the brain are talking to each other in real time," said Greg Simpson, director of the Dynamic Neuroimaging Laboratory at the University of California at San Francisco.While the technology has existed for decades, improved computing power and hardware have recently increased interest in the scanners. There are an estimated 100 MEG scanners around the world -- at a potential cost of $2 million each -- and their numbers are growing.

http://www.wired.com/medtech/health/news/2007/01/72277