A disc or like article (10, 115, 119) rotatable by drive means, such as a compact disc for use with a computer, includes indication means (12, 110, 120) which, when the disc is rotated at or above a predetermined angular velocity, provide an indication that rotation has occurred, which indication can be important if the disc contains confidential information. The indication device can be a tube formed with two enclosures separated by a breakable membrane (15, 16, 112, 122), a colored liquid/gel (17, 111 121) being in one enclosure and passing into the second enclosure, by breaking the membrane, when the disc is spun, thereby providing a visual indication thereafter of the spinning having occurred The invention also relates to such an indication means, per se, for after-fitting to a disc recorded on by spinning, and to a method of producing a disc with said indication means.