In the section "Hohlspiegel" of der Spiegel is the following:
Schrottsemmel
3 Stück 0,99 Euro
(Aus der Bäckerei-Werbung in der Südwest Presse)
I'm guessing it must be funny because "Schrottsemmel" is a typo, since "Schrott" means scrap metal. But what is actually intended?