Forgetting about that "Traps Odours From Your Refrigerator" baking soda box in the back of your fridge for possibly a year.
And then not fully sealing a zip-loc bag full of chopped onions.
My juiceboxes smell like onions.
(Upside to having The Plague: husband's response is "Don't worry! I'll clean it up! You'd better keep resting.")