About a year ago before I got Macchi a friend, he was living in a 2x3 with a stand by himself. He was young, not even 6 months old and he used to popcorn and run around all crazy all of the time. I have a mini dachshund, Dunkin who loves to watch my pigs (he can't reach them, if he stands on his hind legs he can just reach over the coro to see in) and he was just a pup at the time and he would get really excited to see Macchi popcorning and running, and stand up on the cage to see in.
This day, Macchi was full of himself, running and popcorning like crazy. Dunkin came up to the cage and stood up to watch Macchi as usual, and he barked at Macchi (Macchi grew up with Dunkin, he is never phased by the noises the dog makes). Macchi, being the little bugger that he is, ran right to the edge of the coro and chomped right down on the dog's nose! It was the funniest thing I've ever seen, and now Dunkin has a healthy respect for Macchi, and doesn't put his nose through the cubes anymore lol.