An old joke about Superman, but very nearly the best ever, except for maybe that Wonder Woman & Invisible Man one.
From Plop! #5, 1974. Hosted by Cain and Able of House of Mystery/Secrets and some witch from one of the other horror books, Plop! was a gross-out humor book published by DC in the 1970's. It consisted of short and feature-length gags somewhat in the style of MAD, Cracked & Crazy. Plop! was different in that it did not directly parody popular media like films and television shows as the other books did. The title was also a departure from formula...it was a sound effect and not a statement of mental stability. As a side note, I think that Cracked may have had contractual exclusivity on the image appearances of the Fonz and the Happy Days gang in the 70's, considering he was on the cover nearly as much in that period as Alfred E. Neuman was for Mad.
During it's 24-issue run Plop! featured art by Basil Wolverton, Bernie Wrightson, Steve Skeates, Wally Wood, Murphy Anderson and others. The title's most frequent contributor was Sergio (Groo) Arragones, who supplied the border art and most of the framing sequences.