Yamazaki Whisky with Banshaku Ice Balls
They don't melt as fast as our inferior American ice cubes, so they keep the drink at an optimum temperature longer without watering it down as much. An important Banshaku ("evening drink") ritual in Japan, apprentice bartenders in the high-end joints there must learn to carve them flawlessly from big blocks of ice.
They don't do that here unfortunately, but the MoMA store has a stock of imported plastic molds that do the trick quite well (right). You need a bottle of Yamazaki to get the full Land of the Rising Sun effect, though; their 12-year-old is $40 and 18-year-old is $100.