Watch Out for That Thagomizer!
The thagomizer mentioned above and in the article refers to the four-spiked tail of the stegosaurus. The piece even reveals the origin of said term, and is quite enlightening about other stuff as well. The article talks about how Allosaurus and Stegosaurus have links that have been discovered through the stegosaurus's bony, spinal plates.
Interesting stuff, and food for thought, as usual. :)