Cigarette smoke is trapped under two glasses. The surface under the glass on the right was warmed, creating convection currents in the smoke.
Dish soap on a pool of food dye drops the surface tension of oobleck, which pulls the spread of the dye.
Surface tension driven flow. Dish detergent dropped on food coloring in milk reduces local surface tension, which pulls the dye to the edges.
Soap lowers the surface tension of milk in the center of a shallow dish, resulting in food dye being pulled towards the edges
