We've seen these big, floating orbs on occasion in super fancy cocktails at super fancy bars. Gourmet has a good reason why you should use them (not just for looks) and a not-too-expensive source...
Spheres have less surface area than cubes, so they melt more slowly, diluting your drink less as they keep it cold. Also, they really do look cool—especially sitting in a double old-fashioned glass where the sphere almost touches the sides.
Gourmet recommends a set of trays you can buy at the MoMa store for $16. Pricier than your average ice tray, yes, but maybe worth it if you're having a cocktail party where you want to impress your guests.
• Read: Another Round, at Gourmet
• Buy: Spherical Ice Tray Set, $16 at MoMa
(Image: Romulo Yanes for Gourmet)