DC published any number of backup features during the Silver Age. One of my favorites was Roy Raymond, TV Detective. Raymond was the host of a TV show called Impossible But True, and the focus of the stories was how he managed to keep from being hoaxed by people wanting to get on the show for one reason or another.
The stories were always tight, as was the artwork by Ruben Moreira, who handled the feature from its debut in Detective #153 (November 1949) (where it bumped the long-running Slam Bradley) to its last appearance in Detective #292 (bumped in the next issue by the arrival of Aquaman).
Just to give you the flavor of this series, I'm going to present the supposed impossible but true thing, and Roy's solution for a few issues in a row:
Impossible But True: A man from Saturn arrives and shows Roy that it is safe for earthlings to live on his planet. A murderer arrives and plans to hijack his way aboard the alien ship.
Roy's solution: It was all a plot for the murderer to make his getaway on Earth, secure in the knowledge that everybody would think he had departed for Saturn. Roy suspected the man from Saturn was a phony because of a mistake he made in drawing Roy:
Impossible But True: A native African can protect people from attack by animals with special branches from a tree he has blessed.
Roy's solution: It's a plot by one of the partners in a diamond mine to convince his partner to go out in the jungle with little protection other than a useless branch:
Impossible But True: An actress in a movie drinks a potion that is supposed to be able to turn her into Cleopatra. After drinking the potion, she suddenly is able to locate ancient ruins that only Cleopatra would know.
Roy's Solution: The whole think was a scheme by the Egyptian government to flush out an illicit dealer in rare antiquities. He knew the actresss didn't really turn into Cleopatra because:
Impossible But True: An auditor is hexed after touching a stone idol hundreds of years old, with pearl eyes.
Roy Raymond's solution. The whole thing was a plot to prevent the auditor from checking the books of two companies whose bosses have been embezzling funds. He knows the idol is fake because: