Serious on the rocks drinkers prefer ice spheres due to their reduced surface area; the ice melts slower, meaning a less watered-down beverage. A Japanese company called Taisin [Google Translation page] has created a contraption that will create perfectly round balls of ice.
You place a chuck of ice inside Taisin’s Ice Mold, and as the ice melts the press will close around it creating it’s spherical shape. Extract the ice, and voila! I perfect, seamless ball. The Ice Mold can create 30 to 40 ice balls per minute.