Did you know Pogo, the comic strip that inspired greats like Bill Watterson and Jeff Smith, had an animated release? Here's the Chuck Jones directed special that was made in honor of Pogo's 20th birthday back in 1969.

Part II
Part III

There were two other notable Pogo animations, a stop motion film and a public service announcement, but both of these offerings are next to impossible to find. If anybody has a link, feel free to share in the comments!