I never heard of the word until a couple months ago, but there are websites devoted to people asking who, what, and why. They have been spotted virtually everywhere around the world. But every government is saying they don't exist (like UFOs). This year I've noticed a lot more of them in the Boston area. "Chemtrails" are the vapor stream that comes from jets. Usuallly this vapor dissipates quickly in the air, but these "chemtrail" vapors are like streaks across the sky, sometimes intersecting. Sometimes with designs. And they are something like sky-writing because they stay in the air for hours. Weird. Some people say it is the government protecting us with antibiotics. Others say it is the New World Order trying to kill us off. I'd like to think it's the former, and it does make sense because this way the US Government can spread anthrax and smallpox protections without having to worry about any nasty lawsuits from those who have adverse reactions. Or the asphault roofs that get damaged.