Alex Nino - "Drinkers of Dust" (Fantagor Press 1989)

"Drinkers of Dust," drawn by the legendary Alex Nino (Philippines 1940 -  ) and written by Jan Strnad, was published as a backup feature in Richard Corben's Den #8 in 1989.  Nino is well known for his striking black and white ink work, but "Dust" shows off his highly individualistic approach to color as well.  Nino has a wild, impressionistic palette here, and rather than using his trademark black ink at all times, he leaves a surprising amount of the rendering and modelling to the color work.  

Charles Vess - "Cry of the Wendigo" (Amazing Spiderman #277, Marvel Comics 1986)

In 1986, Charles Vess (American 1951 -  ) wrote and drew an unusual backup feature for Amazing Spiderman #277 (maybe most unusual was that this backup was 2 pages longer than the main story.  I'm assuming there was a deadline glitch that led to its existence).  Vess was more a part of the Heavy Metal/Epic Illustrated scene, and his mainstream superhero interior work is rare.  Stylistically, Vess' work here stands out among the other Marvel artists of the time with his delicate lines and the dynamics of Spiderman's black suit against the stark white snowy background.  This story led to Vess' fully painted Spiderman: Spirits of the Earth graphic novel in 1990.