Gnomish Magnetic Plate (NWN)

Like so many gnome inventions, this marvel of ingenuity had its origin in a profoundly stupid idea. Engineers needed a way to clean up the tacks that were cluttering the floor of their workshop. In their effort to create a field that repelled metal (thus sweeping the tacks into the corners), they instead discovered a field that repelled magic. Once they got over their disappointment, they began mass-producing the suits and selling them to their neighbours.