Flow visualization can contribute strong messages of science content within our community of fluid dynamicists, but when communicating outside our community it is the aesthetics of fluid flows that carries the greatest weight. This talk will include a short background of aesthetics in an art history context, and then present examples of four aesthetics: beauty, power, destruction, and oddness. Each aesthetic will be illustrated with examples drawn from flow visualizations from both the Flow Visualization course (MCEN 4151) and sources on the web.