From Portland, Oregon-based Pigeon Toe Ceramics: Ceramic Disc String Lights featuring a set of ten or 25 hand-thrown porcelain shades with glazed interiors in the color of your choice; measuring 11 feet long (the bulbs are spaced every 12 inches).
While the lights are suitable for outdoor use, I wouldn't hesitate to use them indoors.
Above: A string of white ceramic disc lights.
Above: The Ceramic Disc String Lights (shown in citrus) are $224-$550, depending on length, from Pigeon Toe Ceramics.
Above: If one bulb burns out, the others stay lit.. The string of lights has an end-to-end connection; you can connect up to three strands to one another.
Above: The lights are available in 13 colors.
(N.B.: This is an update of a post published Aug. 16, 2010.)