In 1966, Topps released a 44 card set of Comic Book Foldees which featured pictures of DC Comics superheroes. The gimmick was that each card was folded and scored so that you could fold the top or bottom of a card over to make a new, funny picture. Topps originally released cards in this format in the late 1940s and sold several different versions with various themes through the 1970s.
Each 2-1/2″ x 4-1/2″ card in the series can be folded into 9 different configurations, most of which are pretty goofy. Several of the cards have Superman or Superman-related characters. Because of the way they are folded, they’re tough to find in great shape. The art in the set has been attributed to Wally Wood in a few places I’ve found, but the images of Superman and Martian Manhunter in the circles sure look a lot like the art of Justice League of America artist Mike Sekowsky.
Here’s an original wrapper. I don’t know how many cards were originally sold in a 5-cent pack. I’ve seen a British version of this wrapper with a 3p price.
Here are a couple of the cards from the series. I only have a couple of these because they’re pretty hard to find in the wild, though there are usually a lot of them on eBay at any given time.
Here are a few examples of what they look like folded:
The Vintage Non-Sports Cards Chat Board has a number of excellent galleries, including these Topps Foldee galleries:
Lostwackys.com has a gallery of 1976 Topps Mad-Ad Foldees, similar in style to Wacky Packages.