Jim Henson produced some short films for Sesame Street in which Limbo (voiced by William "Rosko" Mercer) counts up to a number and back down again. Limbo was only actually seen in the 10 segment; the entry for the number 4 uses only narration and computer imagery. The films were animated using the Scanimate process at Computer Image in Denver, Colorado in 1970. Jerry Juhl wrote the scripts.