You have some content. A forbidden meme, an article with dubious copyright, a "secret" message. Where do you put it, to keep it available, but avoid those annoying letters from attorneys?
1) Find a stable, long lived Wikipedia article, with plenty of history (preventing the knee-jerk instinct to delete the article).
2) Edit the article, adding your content. (Discretely, or blatantly, mostly depending on whether or not you want the message to avoid attention.)
3) Immediately revert your revision.
4) Capture the URL of your revision. This is your content pointer. The difference between your version and the versions on either side is your message.
Bonus points for hiding your message as a series of sequential typos that look innocuous, but are apparent when looking at the revision comparison.
This is extra-special, because lawyers don't seem to recognize that wiki history exists. If the current page is lacking the thing they don't like, they tend to be satisfied.
Wikipedia may have some mechanism for admins to delete specific revisions in its history. In widespread use, wikicaching would certainly disclose such a feature.