16. Welcome home
If you feel you are intentionally placing balloons next to someone, one of the most evil things you could do for them is. Think about it again. If you want to tell your roommate that he is so beloved at home that his arrival at the door justifies a party, then this is the way to go.
Even though they are harmless and usually contain only some confetti, these party popper bottles make the bang when the string is pulled. You better hope that the recipient of this roommate is not easily excitable. Otherwise, you may expect your food to be on the sidewalk and in the block.