Editor Jake Ward demonstrates how to use an old plastic container and a can of air to take a beer from lukewarm to mountain-stream cold in just a few seconds. (For another video of this project, visit sonicIntoX’s channel at Metacafe.)

Downsize your pocket cargo with a custom-fit keychain. Editor Sean Captain ditches the ring and uses more tool than necessary to trim a small bolt to just the right size for his set of keys. (For a slightly different take on the project, see the site that inspired us: carlitoscontraptions.blogspot.com).

Satisfy your scientific curiosity and your craving for some Frosted Flakes. Editor Mike Haney shows you how to use an old cereal box and a CD to build a device that reveals the hidden rainbow inside any light source. Find more examples of DIY spectrometers over at Wikipedia.

In the age of mp3s, most people have a lot of old CDs lying around. Instead of throwing them in the trash, though, you can put them to use in a way that's both eco-friendly and healthy. Thread the discs onto the ends of a thin metal rod and secure them in place with bolts to make a usable (and cool-looking) dumbbell. Tape up the middle of the rod to provide a comfortable grip, and you'll be all set for a workout.

Submit a 5 Minute Project for Popular Science! Each month we feature a cool and handy new project, and we're excited to showcase some ideas from the inventive Instructables.com community, and our own.

World of wires got you down? Clear the clutter with your very own fire-proof gadget charging station. Editor Mike Haney shows how a power drill and some tape can transform a bread box into a pint-size panic room just for chargers.

About to chuck that busted CD? Not so fast, young grasshopper. Web editor Megan Miller demonstrates three ways to resurrect those scratched discs using stuff you probably already have sitting on your shelf.

When you're vacationing on a beach, nothing beats an underwater camera; but watertight cases are pricey and disposables have lousy quality. Lucky for you, the editors of PopSci have come up with an easy workaround using something there's probably already plenty of in your suitcase (hint: not socks). That's right, thanks to the magic of unlubricated condoms, you too can transform your point-and-shoot into an waterproof wonder. The set-up is easy enough, but as John and Doug demonstrate, it really does help to have a partner lend a hand.

We first became acquainted with Mrs. Daftari's fifth-grade class earlier this year when they rose to a challenge printed in PopSci by submitting their essays for how they'd change the world. Most recently, they sent us these video responses to our 5-Minutes Projects series. In the second, McKenna Mooney and Madison Wilson replicate Megan Miller's DIY non-Newtonian fluid (otherwise known as slime). And in the first, Kacie Moore and Olivia Johnson present a project of their own: the sound catcher.

Sure, external hard drives aren't exactly scarce these days, but while the price point has come down a lot, they're still not cheap. Enter the hard drive case. For just a fistful of dollars, you can pick up a case that (almost) instantly transforms your old internal hard drive into a new storage unit. As Deputy Editor Jake Ward demonstrates here, putting it together is a piece of cake. In the end, you'll have a great-working hard drive, not to mention a few dollars more. Just, keep an eye out for the tiny screws.

Usually our 5-Minute Projects involve soldering and LED lights and other such electronic accoutrements, but this week we decided to skip the fancy stuff in favor of an old-school science project: making rheopectic slime from Borax and glue. This is a pretty safe experiment even for kids--just make sure to do it with parental supervision and keep the Borax, slime, and any fingers that have been touching the aforementioned items out of eyes, noses and mouths.

As any informed PopSci reader will know, the iPhone is definitely a game-changing piece of hardware, but it's not without its problems. Chief among those nagging little imperfections, for me, was the recessed headphone hack that rejected any headphones but Apple's trademark gleaming white buds. Apple's 'phones aren't that bad, but my Shure in-ear pair is better for blocking out noise on the subway (and my Grado SR60s are better for listening at home). Thankfully, an easy solution to this problem is just a trip to the local Radioshack away.

Ah, the alluring glow of the LED light. Whether you're looking to create a bit of romantic (albeit extremely geeky) ambiance, or you just want to have some extra emergency lighting around the house, a set of mini LED candles is a great thing to have. They also happen to be quick, easy, and cheap to make yourself. In this video, executive editor Mike Haney demonstrates how to do it.

Here we have yours truly demonstrating a quick and easy way to greatly enhance your computer's ability to detect and connect to Wi-Fi networks both near and far with a piece of Asian parabolic cookware.