Your body, as an electro-chemical machine posseses it's own EMF field in relation to the environment.
EMF field strength is accentuated by curvature. The sharper the point, the greater the concentraton of the field.
theoretically, placing magnets at these points (ie fingertips) would increase field-stength and allow a sensitive to more aptly judge the ambient field.
Personally, I feel as if you'd be begging for cancer.