Joel Barnard

You’ve successfully tested the limits of how much can fit into a #10 envelope without bursting its seams, but now you’re questioning how much postage you need. Sure you could just slap a few of the new 44-cent stamps onto whatever you're sending and be done with it, but that’s good money you’re throwing away.

Instead, spend just a few bucks now to build a simple magnetic postage scale, newly updated from an original article in the February 1971 issue of Popular Science.

Our third updated DIY project from the Popular Science digital archives involves luring and then trapping bugs that have managed to find their way inside your house--a truly universal problem. Follow along as we update a circa-1971 trap for today's smarter, more intelligent insects for less than $20.

No doubt you have it on your calendars, but in case you forgot, the 25th is National DNA Day. Can't think how to celebrate it? Well, if you have $68,000 or more lying around, you can bid for a chance to have your entire personal genome sequenced by Knome, a company that does such things.

Legal-ish alternatives to marijuana exist, you just need to know where to look…er, smell. Apparently that’s what someone learned when they put the herbal incense brand “Spice” in their pipe and smoked it. The results were, like, totally rad, dude. It turns out Spice contains the synthetic substance JWH-018, which is incredibly similar to the main active component of marijuana. Although sold legally in many countries, governments around the world are lining up to put the kibosh on the Spice party.

Professional thieves beware! In addition to motion sensors, security cameras, flood lights, rent-a-cops and Doberman pinchers, there’s a new piece of technology designed specifically to ruin your day. And to make matters worse, it’s invisible. Well, not exactly invisible, but stare right at it and you won’t realize it’s there. Worried? Thanks to a novel new motion sensor developed by the Fraunhofer Institutes for Applied Polymer Research IAP in Potsdam-Golm, Germany, you should be.

How long does it take the Earth to revolve around the sun? Did the earliest humans and dinosaurs live at the same time? What percentage of the Earth’s surface is covered with water? Think you know the answers? Well, if you’re an American adult you may be frighteningly alone.

For most of us, procuring a gallon of milk requires only a quick trip to the corner store. Breastfeeding mothers, on the other hand, need an estimated 30 percent more energy to keep a newborn nipper happy with fresh mama juice. Eating like a horse and lazing about are two ways to offset this extra energy demand, but another factor may contribute as well. According to a new study, support from family may play a key role in helping mothers conserve energy and therefore allow their bodies to prepare more quickly for another pregnancy.

You won’t find geolocator backpacks in the North Face catalog anytime soon, but if you fly south for the winter you may notice one strapped to the back of a migrating songbird. That’s how an inventive group of researchers have been tracking the speed and location of purple martins and wood thrushes flying from Pennsylvania to South America and back. What they’ve have found is truly astonishing.

The annoying physical exertion associated with lifting a pill to your mouth and washing it down with a Dixie cup full of H20 could soon be history. Much excitement is building around electronic implants that dispense medicines automatically or via a wireless medical network. According to a team of Australian and US researchers, however, remote Intelligent Drug Delivery Systems (RIDDS) are rife with security issues.