Who's afraid of a little ol' meme?
On Flickr, Arenamontanus has posted a photoset of 19 warning signs from the future, including a few personal favorites, like Memetic Hazard. Memes, of course, were first written about by Richard Dawkins in his breakthrough 1976 book The Selfish Gene: "The term meme... refers to a unit of cultural information transferrable from one mind to another. Examples of memes are tunes, catch-phrases, clothes fashions, ways of making pots or of building arches. A meme propagates itself as a unit of cultural evolution — analogous in many ways to the behavior of the gene (the unit of genetic information)."
With this as context, I suppose you can interpret the black lightbulb in various ways, perhaps as a warning that particularly powerful ideas and thoughts have the potential to be passed on to others in the immediate area. Or, the sign might be a warning about memetic drift (the tendency for memes to mutate as they propagate from person to person), memetic inertia (the tendency for memes to propagate in coordination with particularly annoying mnemonic devices), or even memetic association (the tendency for memes to herd together).
[image: Memetic Hazard]