So awesome. This used to scare the hell out of me when I was a kid...
Available at Profiles in History.
Here's the auction house description:
This iconic effigy was used by the diminutive alien "Balok" in the classic first season episode "The Corbomite Maneuver" to intimidate the crew of the Enterprise. When Kirk later asks Balok about the puppet, he responds, "My alter ego, so to speak. In your culture, he would be Mr. Hyde to my Jekyll. You must admit he's effective. You would never have been frightened by me." Designed by legendary sculptor/artist Wah Ming Chang who created Star Trek creatures such as the Gorn from "Arena", the M-113 Salt Vampire from "The Man Trap", and the Taurus II humanoids in "The Galileo Seven", among many others. The puppet head is crafted of polyurethane foam and measures 16 in. tall and is mounted on a wooden 1 ¼ in. diameter dowel extending 15 ½ in. below the base of the neck. Three electrical wires and a cable protrude from the neck—the cable to actuate the mouth of the puppet and the wires to presumably control eye movement. Shows some wear in the paint in areas and foam exhibits minor separation from movement of the mouth, typical for such materials from this era. Overall, the polyurethane foam remains in remarkable, supple condition. This alien head is featured in the closing credits of virtually every episode of the Original Series and remains as a symbol of one of the most influential television shows of all time. Certainly, a relic worthy of a toast with a glass of Tranya!