I'd say that the weirdest place I've ever played Pokémon was in my cousin's basement. About a year ago, I was over at a party in my cousins' house and they decided to play hide and seek. Unfortunately for me, they decided to make the basement out of bounds by locking it after I decided to hide in it. Isolated and in complete darkness, I needed some sort of light, found my Nintendo DS in my pocket (don't ask me what it was doing there) and proceeded to play Pokémon Diamond. I managed to get out about half and hour later when they realised I was missing and searched.