At first glance, we thought this was a portable keyhole, and the inventor mentions having lost a keyhole once.  But it's actually practical — an illuminated and magnetized key for finding a lock in the dark.  The text notes that the inventor looks over his glasses to keep the lenses from wearing out, which sounds silly at first ... until one recalls that some corrective lenses actually do weaken the eyes over time, so avoiding them would in fact lengthen the life of the prescription.  As for the claim that the invention also cures hay fever, dusts the piano, makes vacations easy, and does away with sea sickness, we'll give the inventor the benefit of the doubt.  From the Duluth Herald, 1911.