A broad base of knowledge is necessary for the successful solution to applied problems, but on the other hand, developing such practical solutions can open the door to new and exciting adventures in basic research. Several such synergistic events are briefly described. These include the design and development of magnetic refrigerant materials (1) for the liquefaction of H(sub 2) gas, and (2) for near-room temperature cooling and refrigeration; and (3) the design and development of cryocooler regenerator materials. The first led to the discovery of both supercooling and superheating in the same substance (Dy and Er); the second to the discovery of the giant magnetocaloric effect, the colossal magnetostriction, and the giant magnetoresistance in the same substance (Gd(sub 5)(Si(sub x)Ge(sub 1-x)(sub 4))); and the third the disappearance of three of the four magnetically ordered phases in Er by Pr additions in both high purity Er and commercial grade Er.