How To: Make Super Fizzy Carbonated Beverages at Home with Dry Ice

Want to make your own soda or maybe just bring a dull one back to life? Homemade sodas don't always live up to the store bought ones because they can taste flat by comparison. This quick and easy method makes super fizzy drinks with only four ingredients. Because putting dry ice in a sealed bottle would effectively turn it into a bomb, you'll need to make a safety valve for the bottle.

How To: Make These Sonic Distance Sensors for the Bad Driver in Your Life

Today's fancy cars come with all sorts of options, from power mirrors to working seat belts. Some of us condemned to live in the reality of capitalist recession have no car, or perhaps a very modest one. But your modest car can still have some cutting edge technology wedged into the trunk and dashboard if you know what you want and where to look for parts. Today, we make a parking sensor using a sonic range finder, just like in the vehicles our owners drive!

How To: Make Surface-Mount Electronics at Home for Smaller, Cheaper DIY Gadgets

Whenever we make a homemade circuit, we use what are called through-hole components. Any components with long metal leads is a through-hole component. They are great for soldering to, but it's tough to fit enough through-hole resistors and capacitors into a smartphone. To get those last microns, we have surface-mount components for SMDs (surface-mount devices). These are all of those teeny, tiny things you see when you crack open your digital camera or laptop case.

Glass Cutters Are for Tools: How to Dissolve Glass Using Sodium Hydroxide

Glass is one of the least reactive substances known to chemistry. It is the standard container material for almost all lab chemicals because it's so inert. But there are a couple of substances that have strong reactions with glass. Sodium hydroxide, aka solid drain cleaner or lye, can easily be stored in glass as a solid, but when molten, it reacts violently with glass and can actually dissolve it away! So, the next time you clog up your drains with broken glass beakers and flasks, rest assur...

How To: Wildlife Photography with a DIY Motion-Triggered Camera

Even if you live in a big city, chances are you have some wild raccoons or foxes that cannot abide a vertical trash barrel. While apparently omnipresent, these phantasmic critters usually vanish in the night leaving only a shameless trail of refuse you never wanted to see ever again. While I haven't found a way to stop them, I can help you snap some photos of the dastardly creatures.

The Sweet Smell of Success: DIY Smoke Mix with Sugar and Potassium Nitrate

I finally got around to trying out another one of Will's mad science experiments and found out that this one was actually more satisfying (and less frustrating) than my slightly uncooperative jar jet. There's something very pleasing about making potassium nitrate at home in the kitchen and then watching the transformation from semitransparent liquid to spiky, frozen crystals. That was the best part for me, second only to igniting it with its sugar companion.

How To: Send Your Secret Spy Messages Wirelessly Through Light with This DIY Laser Audio Transmitter

Looking to transmit some super-secret audio communications to your other spy buddies? A laser is the perfect tool for getting your sounds heard from a small distance—without anyone intercepting them— even if it's just a cover of your favorite pop song. A laser audio transmitter uses light rather than radio waves to transmit sound. This is a much more secure way to send audio communications because the laser is a focused beam of light, whereas radio waves are not controlled, so they can be pic...

News: This Real-Life, Working WALL-E Robot Is Absolutely Perfect (And Built Entirely from Scratch)

Want to build your own life-sized, working replica of WALL-E? Be prepared to take on a second job! Mike Senna spent two years perfecting his own version, working 25 hours a week and totaling somewhere around 3,800 hours for the whole project. He had no blueprints to go by, so he spent a lot of time watching the movie over and over to get everything just right. The video below shows some of the construction; skip to about the one minute mark to see WALL-E in action.

Robot Basics: Using an H Bridge to Move Your Bot Backwards

I love robots. They have the potential to evolve into Asimovian destroyers of the human species, but have only just mastered the art of cleaning my rug. They have an ever increasing cool factor and a growing number of cheap and simple components that let the hobby roboticist reach for the burning miasmas of plasma. But to get to the stars, we need to start with the basics.

News: Explosive Polymerization Is Basically Magic

This video is by Adrian McLaughlin, aka plasticraincoat1 on YouTube, who shows us one of the most magnificent examples of explosive polymerization ever. In the video, what appears to be about 1/2 tsp of p-nitroaniline (which is short for para-nitroaniline, which is also referred to as 4-nitroaniline) is treated with a few drops of concentrated sulfuric acid, in a ceramic dish, over a Bunsen burner flame.

How To: Make a Simple Fog Machine to Prank Your Roommates

Like theme music, I always feel that I need more fog in my life. Fog can be useful for many reasons—warding off smaller siblings from your bedroom, keeping curious hands out of your cupboard, and tricking your friends into thinking there's something horribly wrong with their vehicle. So, today we'll be making a very simple fog machine for small scale applications.

How To: Stop Bike Thieves Dead in Their Tracks! Make a Magnetically Controlled Bike Alarm

Bikes are a great form of transportation. They use human energy more efficiently than any other machine. You can keep it in your closet or hallway. You can even take it on the train in a pinch. However, this portability is also the bike's biggest draw back. If you own a bike in the city, chances are it will be stolen. Locks barely deter thieves armed with bolt cutters and crowbars. Throw the bike thieves for a loop and make a tilt-sensitive alarm. It will hopefully startle your bike's assaila...

Contest: Potassium Nitrate Crystals

Recreating one of Will's mad science experiments, I made some potassium nitrate crystals. This was definitely the most fun part of my DIY smoke mix. I can't win the contest, but I'm just putting it up here for fun, since I liked the pictures so much.