I feel like the Pioneer Plaque, an engraved rectangular plate on a spaceship sent from earth to outer space, is a little dumb.  I get the idea:  Find a way to communicate the existence of human life in our solar system, as well as a few tidbits of our knowledge of universal things, to an unknown civilization that has absolutely no way of understanding our language, culture, or anything about us.  But at the same time, it seems to me that if a relatively intelligent human (myself) can't understand what it means, it kind of misses the point. 

It reminds me of Darwin's Tree of Life illustration, which people get tattooed on their bodies, permanently.  I get that it's a historically significant drawing and all, but there are way better methods of representing that kind of information, especially now that it's not the 1860s and we're not living on a boat.