Abstract: The holder has a base which can be rotatably attached to at least one chair leg, where the chair leg can be a leg of a star-based chair, a leg of a four-legged chair, an upright of a wheel chair, and analogous members of other chairs. An adjustable height arm is rotatably attached to the base, and a deck for holding a keyboard is rotatably attached to the arm. The holder can be adjusted easily in height, distance from the person using the holder, and angle of the deck, and the holder can easily swing away for easy access to the chair.

Abstract: The new fastener has a shank which is resiliently compressible along an axis perpendicular to the shank push-in axis and has teeth protruding from the shank along the axis of resilient compressibility. The teeth are inclined in the push-in direction and in the pull-out direction. When the shank is pushed into an existing screw hole, then inclines of teeth just past the far side of the screw hole are increased to resist motion in the pull-out direction so that the shank is secured in the screw hole and so that the fastener can be pulled out without damage. The shank is configured to increase the compressibility and to increase the elastic force opposing compression. The shank can be a monolithic part of a first structure fastened to a second structure.

Abstract: The new fastener has a shank which is resiliently compressible along an axis perpendicular to the shank push-in axis and has teeth protruding from the shank along the axis of resilient compressibility. The teeth are inclined in the push-in direction and in the pull-out direction. When the shank is pushed into an existing screw hole, then inclines of teeth just past the far side of the screw hole are increased to resist motion in the pull-out direction so that the shank is secured in the screw hole and so that the fastener can be pulled-out without damage. The shank can be integrally part of a first structure being fastened to a second structure.