Correlated Magnetics developed a printer that is able to “print” magnetic patterns into rare-earth ferrite or flexible magnetic materials. This allows them to code magnets uniquely so that a given combination binds only to its counterpart.
http://youtu.be/jcCx8J5rP6U
Special patters generate unique functions
http://youtu.be/oBHWUUtJH6U
http://youtu.be/65XwNwgyWO4