Hard to Escape the Spam

After some months of spam-free email, I've been lately getting an impressive array of ads for "on1!ne 4arm@ceut1c@ls" or some such. As annoying as spam is, I'm also fascinated by it. Why, for instance, did this morning's message include this text (from the Lord of the Rings The Hobbit [thanks, Jim!]!) at the bottom, below the jpgs of various anti-impotence drugs?

swordsman.
The elves were the first to charge. Their hatred for the goblins is cold and bitter. Their spears and swords shone in the gloom with a gleam of chill flame, so deadly was the wrath of the hands that held them. As soon as the host of their enemies was dense in the valley, they sent against it a shower of arrows, and each flickered as it fled as if with<

Is it just a lark? Does it help defeat spam filters? Anyone out there know more on the theory and practice of spamming?