My organic chemistry lab during my time at university showed me the power of Hydrazine. The instructions clearly stated: "Do not heat over 70 °C!"

Well, the group next to me didn't quite manage it, I only heard "Oh oh!" followed by slamming shut the fume hood's front and a Boom! when the distillation apparatus and peripheral glass ware disintegrated. That only amounted to 1,000€ in damage, though.