Stained Glass by Kent Brewster (@kentbrew)
Stained Glass was the inspiration for Nick Schlott's Tesserae, which came out in 1991 for Macs, DOS, Nintendo, and many other platforms. You'll need a PC with DOS 2.1 or later, 256k RAM, and 75k free space on your hard disk to run Stained Glass, and anything running Windows for Tesserae.
See SG.DOC or Kent Brewster's Butt-Ugly Home Page for more.