A couple of years ago in December I recorded a video of some amazing vortex action in a big glass of water on my kitchen counter. Every time I show this to a friend they are mesmerized by the whole thing. I was first inspired by a toy vortex cannon my wife bought me the year before as a fun gift. I tried a few times to blow giant smoke rings using my crappy old fog machine but that never really worked out. Then one day I accidentally spilled a single drop of milk into a sink full of water and I was amazed by the shapes formed by the milk as it swirled downward.
The very next weekend I got set up on my kitchen counter with three big Halogen lamps, my tripods, a cardboard box, some felt, and a nice big glass of water. I started off with white drops against the black background and then later I switched over to a bright white background. The drops were a mixture of cream and milk, and I really liked how they sometimes appear just a little bit clumpy. Once I started with the drops of colored dye then the black background did not work for me at all. I made up a white background from a few sheets of nice heavy paper from my wife's printer upstairs. The bright white background was perfect as I could adjust the amount of dye in a drop and thereby control the transparency of the resulting swirl that occurred in the water.