An important but forgotten component of The Funtastic World of Hanna-Barbera anthology block was the interstital feature known as HB-TV. What the producers did was mash together various clips and set them to a specific song.
For example, the following video features clips from Scooby-Doo and The Flintstones, among others, to the beat of "Somebody's Watching Me", by Rockwell & Michael Jackson, the actual video of which was posted over at The Land of Whatever recently. KanandaRhodes uploaded this video to YouTube:
In recent years, Cartoon Network has revived the concept, but instead of using established pop songs du jour, they've used original material or remixed archived music. However, they haven't tried anything like that in about 10 years, another example of the current regime having no clue.