These aren't the types of black holes you find in space, but that doesn't make them any less spectacular. Swiss photographer Fabian Oefner's "Black Hole" series shows "paint modeled by centripetal force."
Each "black hole" image is created using a metallic rod connected to a drill. Different colored paint is then dripped on the rod. The drill is flipped on, and within the blink of an eye, the image is created. It sounds simple enough, but man, is it ever messy with all that paint flying all over the place.
Oefner says each image is captured "one millisecond after the drill is turned on." In order to catch the paint spinning, Oefner used a slow-motion camera and a special sensor that synced a bunch of flashes together at 1/40,000th of a second. Here's a video showing how he made them:
Oefner's work can be purchased as prints, or admired in the gallery below.