At school I synthesized a tiny amount of NI3 (nitrogen triiodide). As it was late and the substance was still dripping wet I went home leaving it under fume hoo

At school I synthesized a tiny amount of NI3 (nitrogen triiodide). As it was late and the substance was still dripping wet I went home leaving it under fume hood to dry. Next day I learned (to much amusement of my chemistry teacher) that it scared the hell out of a cleaning lady who managed to trigger it off accidently while cleaning the chemistry lab.