Self-heating soup sounds like something from the future: Push a button on the can, and three minutes later the contents are piping hot. But it’s widely available today, along with self-heating coffee and hot chocolate. In Japan, I even found self-heating sake. Pretty high-tech!

Or not. In fact, these products use a chemical reaction known since at least 4000 B.C.—the mixing of quicklime and water. When you roast limestone at about 1,650°F, it converts to quicklime, a powder used to disinfect corpses in war zones. Mix quicklime with water, and it grabs and binds the water molecules, releasing lots of energy in the form of heat. (The material left over, known as hydrated or slaked lime, is the basis of lime mortar, popular in the Roman empire and still used today.)

Soup is OK, but I decided to use the technology to make a self-heating hot tub.

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Oxygen is a good thing. Oxygen is life. But if it were much more than one fifth of our air, we’d be in serious trouble. The other four fifths is nitrogen, an almost completely inert, obstructionist gas whose main effect is to get in the way of the oxygen, especially where flame is involved. For every bit of oxygen a fire consumes, it has to heat up and push away four times as much useless nitrogen. With pure oxygen, that damper is gone, and things that merely smolder in plain air go up like dry tinder. In 1967 three Apollo 1 astronauts died in a raging fire when Velcro lit up in their pure-oxygen pressurized space capsule.

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There are many unusual things to see around Newton Falls, Ohio—the Wal-Mart with hitching posts for Amish buggies, the Army base with helicopters and tanks proudly arranged on hills—but I was here for the most unusual thing of all: the local Dynamitron. I was here to make frozen lightning.

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How will other materials hold up under the grinder? Launch the gallery here to find out.

In the early 1900s, the element radium was so popular, it became a marketing term. Luminous watch hands used radioactive radium, but Radium-brand butter, fortunately, did not. Today, titanium is the new radium. Everything from credit cards to crowbars is advertised as having the strength of titanium. How many products actually do?

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I think Apple sells fantastic objects that look like they came from the future. And apparently, in that future we all live in velvet rooms and have no fingers-there´s no other way to explain the ultra-shiny mirrored backside of my new iPod nano, which got scratched and grungy with fingerprints in exactly three seconds. So I gave it a nifty scuff shield and, while I was at it, my own logo, using a superthin layer of electroplated copper.

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I was 10 years old, but I'll never forget that day: The smell of bread in the oven. The crunchy grit of steel wool in my fingers. The fact that my mom still left matches out where I could find them. That's when I learned that, yes, you can light steel with a match.

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Preserving a Snowflake in Superglue

Cost: $10
Time: 10 minutes
Easy | | | | | Hard

How It Works

1. Set microscope slides, coverslips and superglue outside when it's snowing

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