I've been thinking of a pop culture reference for today's post. I was mulling the thought of using a Tolkien-Aragorn reference, or perhaps a Twilight-Vampire comment. Instead, I'll just let you know that pearlescent paint/ink has some great potential for demonstrating fluid dynamics.
Mix a water-based pearlescent paint (this one is probably made with powdered aluminum) with water and stir. Watch lovely Von-Karmen vortices whirl about. See the transition from laminar to turbulent flow. All this can be yours for a few bucks worth of paint.
Or, if you're so inclined, mix a very thin suspension in water and then use the glittery parts to help track where the water goes.