Bucky cubes are square Bucky balls, which are also entertaining and will make you smile. Whether you prefer the cubes or balls, the tiny pieces of metal are magnetic and fun to twist about in your hands or form into shapes. The magnets stay together as you change the pattern, so you can make practically any shape with them. The toys are mesmerizing, so be careful of getting too distracted by them. Playing with Bucky balls while on the phone or while hashing out a problem may help improve your concentration and give you a little hand workout, though.