When Poppy my neo was a youngster (about 4 months) she saw me take the bag out of a really old cylinder vacuum cleaner and as I went to the dustbin to empty it, she couldn't resist a look inside the machine.
As she's got so much excess skin around her neck, her head went in fine, BUT WOULDN'T COME OUT AGAIN! So, in a fit of panic, she ran around the room wildly with this machine stuck on her head until she proceeded to bang into the wall, pressing the 'start' button and setting the vacuum in motion!
As Pop flung herself around the room (scaring the life out of me) our other dog Diesel came flying in, ready to attack this monster that was 'humming' it's way around the house with dust coming from one end and a decidedly thicker, brown stuff falling from the other!!!
Luckily I was able to evict Diesel before any damage was done to Pop, but then there was the task of removing the vacuum. After much un-screwing of screws and consideration of calls to the fire brigade, common sense prevailed and I realised that if her head went in, it HAD to come out. So, gentle prising and pulling of her dewlap (the skin under the chin) and her chubby cheeks, eventually resulted in the unveiling of one very scared puppy with bulging eyes, foaming mouth and a life-long distrust of vacuum machines. (She slept for about 12 hours after that particular ordeal!)