Computer programs are provided which utilize a touchscreen to emulate three-dimensional objects on a two-dimensional computer screen. One program, called personal cardfile (PCF), combines the convenience of a desktop rotary cardfile with the power of a computerized product. PCF presents an image of a rotary file, complete with "knobs" for flipping through "cards" in a cardfile, and "tabs" for selecting "cards" to be represented individually on the touchscreen. Another program, called financial computer (FC), emulates an HP12C handheld financial calculator. The HP12C calculator is manufactured by Hewlett-Packard Company, Palo Alto, Calif. On a computer touchscreen, an operator sees a familiar looking "calculator" and touches its "keys" to operate it, just as for a conventional three-dimensional calculator.