According to the pilot, his glider's heading differed about 5 degrees from that of the towplane, when the towplane began its takeoff roll. The pilot used rudder to correct but the glider dragged a wing, and yawed 70 degrees to its right as a result. The glider lifted 3 to 5 feet above the runway, the pilot released the tow, the glider touched down in a sideslip, and the resultant side load on the tail landing gear "buckled the tailboom 90 [degrees]." The pilot reported that there were no mechanical deficiencies with the glider that would have prevented normal operation, and that the accident might have been prevented by ensuring alignment of the glider with the towplane prior to the takeoff roll.