404. Baboon Adopts Bush Baby
406. Dog and Monkey Wrestle

It's the most literal piggyback ride we've ever seen. (Get it?) In the animal kingdom, monkeys and pigs are not a likely pair. One lives in tropical locations and likes bananas, while the other lives on farms and eats slop until it's fat enough to be eaten. Which is likely why, when this ridiculously addictive video of an adorable baby monkey riding on the back of a piglet went viral in September 2010, the Internet went, "Awwww." Soon after that reaction, the Internet went "$#*!" when it realized that the accompanying song, penned by Parry Gripp, was still stuck in heads days later. Watch at your own risk.