Remember all the hullabaloo about Net censorship? Well, a while ago, comic books went through the same thing. In 1954, a censor called the Comics Code Authority was created to quell public concerns over inappropriate material for comic books to protect children.
Comic publishers had to submit their comics and get approval from the CCA. The requirements were pretty strict (for example "in every instance good shall triumph over evil." Zombies, werewolves, and vampires were a no-no).
In 1971, Spider-Man creator Stan Lee was approached by the US Department of Health, Education and Welfare to do a comic book tale of the dangers of drug abuse. But even though drug abuse was portrayed as a bad thing, the inflexible CCA didn't allow it (after all, the rules prohibit the mention of "drugs," period.)
What happened next made comic book history. Here's Stan Lee telling us in an interview with Comics Alliance about how he went against the CCA and published the comic book anyway: Link [embedded Flash video clip] - Thanks Brian!