When I was a freshman, there was a horrendous smell in our dorm one day. We called Security because we thought it was a gas leak. They assured us we didn't have gas in the building, but sent somebody out to investigate anyway. The tech walked in the hall and said, "Holy shit! There is a gas leak!" We evacuated while they investigated. Long story short, there was an Asian kid on the hall upstairs who had shipped in some durian and left the remains in his trash can.