I've been thinking. You know how each type has its own properties? Well, one property I've thought of is the smell of a Pokémon's farts. Does the smell have to do with the Pokémon itself or its typing? If it's typing, then I can imagine some of the smells would be like this:

Normal: A basic fart
Grass: Decaying plant matter
Ghost: A rotting corpse
Water: Rotting fish
Fire: A subtle smokiness
Poison: So intense that it makes you vomit and faint
Ground: A subtle earthy smell

I can't think of any others.