A composite image showing a US $1 banknote covered with bacteria. The banknote was imprinted for 5 minutes on agar gel, which contained a nutrient medium. Various bacterial colonies developed after 4 days. They were pooled and prepared for scanning electron microscopy (SEM). Images of the bacteria were superimposed on the image of a $1 banknote. Bacterial colonies growing from the banknote imprint indicate that germs were present on it. This conceptual image shows that banknotes harbor germs of microorganisms and that it is a good idea to wash one's hands after handling paper money. Enhanced combination SEM. Image width: 13.94 micrometers. Magnification of the bacteria: 7,175x if the image is printed 10 cm wide.