These creative cups by Tale Design in Korea feature a carefully sculpted bulge on the inside that ensures that each sip of your (preferably white and opaque) drink will reveal a different phase of the lunar cycle.
The black cups go perfectly with white drinks like milk or nigori-zake, an unfiltered Japanese rice wine with a cloudy appearance. For tea drinkers, there are white cups as well. Their 2-piece sets go for $24 and $30 on their website (for small and large cups).