Curing--or even delaying--cancer has become a Holy Grail for medical research.

FORBES

Robotic surrogates that offer paralyzed people the freedom to explore their environment, manipulate objects or simply fetch things has been the holy grail of BCI research for a long time.

BBC: The robot that reads your mind to train itself

Finding it in living players is considered by many researchers to be the "holy grail" of concussion research, according to Bailes.

CNN: Scan may detect signs of NFL players' brain disease