The pilot of a tailwheel-equipped airplane reported that during the day he practiced several landings with no anomalies. He picked up a passenger and attempted a full stop landing at a nearby airport. Shortly after touchdown, the airplane nose turned slightly to the right. The pilot corrected with rudder input to the left, and the airplane turned sharply to the left. He stated that he could not correct the left turn with the rudder or wheel brakes, and the airplane exited the left side of the runway. The right wing and right horizontal stabilizer contacted terrain, and the airplane came to rest upright. The airplane sustained substantial damage to the right wing and the elevator. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.