This week in one of most famous scientific journals has been published this report: Camara CG, Escobar JV, Hird JR, Putterman SJ, "Correlation between nanosecond X-ray flashes and stick–slip friction in peeling tape.", Nature 455, 1089-1092 (23 October 2008) | doi:10.1038/nature07378 http://www.nature.com/nature/journal/v455/n7216/abs/nature07378.html Abstract: Relative motion between two contacting surfaces can produce visible light, called triboluminescence. This concentration of diffuse mechanical energy into electromagnetic radiation has previously been observed to extend even to X-ray energies. Here we report that peeling common adhesive tape in a moderate vacuum produces radio and visible emission, along with nanosecond, 100-mW X-ray pulses that are correlated with stick–slip peeling events. For the observed 15-keV peak in X-ray energy, various models give a competing picture of the discharge process, with the length of the gap between the separating faces of the tape b...