The helicopter impacted terrain during cruise flight. The pilot reported that the helicopter was established in cruise flight about 500 feet above ground level (agl). He was accompanied by a dog, which was restrained by a harness in the right seat. The pilot stated that a farmer waved as he flew by, and he banked the helicopter 30-degrees to the left and the right in response. He noted that this maneuver upset the dog. He subsequently transferred the cyclic from his right hand to his left hand, and restrained the collective by using the side of this leg, in order to free his right hand to reassure the dog. The pilot reported that during this time the helicopter entered a 135-degree right bank, and he seemed to become "weightless." He increased collective to load the main rotor and rolled left, recovering about 250 feet agl. He noted that the main rotor speed was "very low" and the helicopter was descending rapidly. About 50 feet agl he attempted to pitch up, but the aircraft did not respond. He "pulled all energy out of the rotor" and the helicopter impacted in a slight nose down attitude. The skids collapsed, the lower portion of the fuselage was damaged, and the main rotor blades struck the tail boom during the accident. The pilot stated that there were no failures or malfunctions associated with the aircraft prior to the accident. He noted that the distraction of having a dog in the helicopter and his transferring cyclic control to his left hand were contributing factors to the accident.