Abstract: A free-standing panel assembly includes adjacent panels hinged together by an easily installed hinge mechanism. The hinge mechanism is removably attachable to respective fasteners formed adjacent edges of each of the panels. The assembly may also include a stay mechanism that serves to fix a relative angle between adjacent panels.

Abstract: A rotatable display tower, preferably for use as a merchandising rack for the original sale of packaged products, preferably audio cassette tapes. The tower provides, in a relative minimum of space, a large number of audio cassette tapes to be viewed "head or face on" and, their spines, too. The display tower securely holds the packages, in a tilted-back manner, yet allows the consumer to easily remove the same for purchase.

Abstract: A rotatable display tower, preferably for use as a merchandising rack for the original sale of packaged products, preferably compact discs. The tower provides, in a relative minimum of space, a large number of compact discs to be viewed "head or face on." The display tower securely holds the packages, in a tilted-back manner, yet allows the consumer to easily remove the same for purchase.

Abstract: A display rack for books, cassette tapes, compact disks, LP records, etc. comprises an I-frame support for at least two rotatable towers housed thereon. Two or more I-frames and towers are hinged together with the towers supported therebetween for rotation. With the I-frames connected together an extremely versatile structure is presented which enables the display to assume a wide variety of spatial configurations.

Abstract: A modular system includes a plurality of building units, each having at least one countersunk aperture for alignment with a countersunk aperture of another building unit; and fastening devices for securing the building units together in any of a plurality of configurations to form the modular system, each fastening device including a first bolt for engagement within a first countersunk aperture such that the upper surface of the first bolt is substantially flush with the inner surface of the wall of the building unit containing the respective countersunk aperture, a second bolt for engagement within a second countersunk aperture that is in alignment with the first countersunk aperture such that the upper surface of the second bolt is substantially flush with the inner surface of the wall of the building unit containing the respective countersunk aperture, and a nut positioned within the first and second countersunk apertures for securing the first and second bolts together.