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294 laser-cut wooden pieces that assemble into a marble lift with a hand crank, and once built, ten marbles ride to the top and roll back down through the city. The instructions are good and the build takes an afternoon. Then it sits on a shelf and gets cranked by everyone who visits.
Three hundred microliters of magnetic liquid, sold to speaker builders who use it to pull heat away from a voice coil. It does that job well. It's also black liquid that grows spikes when a magnet comes near, and that's why most orders don't come from speaker builders.
Slide a finger along the stem for pitch, squeeze the cheeks and the mouth opens for a wah. That's the whole technique, and it produces a wobbling electronic voice that has made the Otamatone a fixture of Japanese pop and the internet since 2009. This one is the unicorn version, with low, mid and high range switches. Nobody plays it well at first.
An electromagnet in the ring holds a small globe in the air and a line of LEDs lights it from the frame. Plug it in, hold the globe steady until it catches, let go. It takes a few tries the first time and none after that. The ring is easier to set than the C shaped ones.
No batteries, no cord, no trick past magnets arranged so the top hovers above the base while it spins. Launching it takes a few tries and a flat surface. Once it goes, it stays up a long time, and everyone walking past has to stop and look.
Cold, the mug shows Kirk and the landing party standing in the transporter room. Add hot coffee and they dematerialize, leaving the pad empty. Cools down, they're back. It's from the Unemployed Philosophers Guild, who've been making this exact kind of joke for thirty years. Hand wash it.
A Moai on a nightstand base, with a slot across the nose that holds most frames, from thin metal to chunky acetate. The base takes a phone. It's a spot for the glasses that otherwise vanish before you can find them, and the head looks better wearing them than you'd guess. Stone-look resin.
There's a magnetic stirrer in the base and a button on the outside, and between them they handle the part of making coffee that needs a spoon. Stainless steel, rechargeable, spill-proof lid, and the base detaches for washing. It's unnecessary, and people who own one use it daily.
Plant something with long leaves in the top of this resin head and it grows hair. Three inch opening, drain hole in the base, so it's a real planter and not just a face. The expression it wears is asking for a kiss, and you'll be looking at it every day.
Four inches of antique-style key that opens bottles. It lives on a keyring and nobody notices it until it's needed. An ounce and a half. The disguise is good enough that people ask what it unlocks, and telling them is the best part.
Three small fragments of the Campo del Cielo iron meteorite, which landed in northern Argentina about 4,000 years ago and was known to locals long before the Spanish wrote it down in 1576. Each weighs a gram or three. They come in a storage box with a card. It's a rock, and it's also older than the planet's oldest rocks. Hold it and think about that.
A small square tank, a quiet pump, and a few silicone jellyfish that drift up and down in the current while LEDs cycle through colors. The tank is square on purpose, so the shapes don't warp the way they do behind a curved wall. Fill it with water, plug it in, and it does its thing for as long as you leave it on. Nothing to feed.
A rechargeable, gun-shaped Tesla coil that throws a visible electric arc from the tip and lights a fluorescent tube through the air. There's a voltage meter on the side and a gold-plated panel on the front. It's a science demo with a trigger. Keep it away from phones, pacemakers and anyone who hasn't agreed to be in the room.
Bigfoot is three and five eighths inches tall, made of vinyl, and lumbers across a table with what the listing calls sass. Archie McPhee has made things like this for decades. Wind him up, put him down, and stop working for a while.
Two powders, a beaker, and water: mix them and the beaker fills with cold blue light for a few minutes. It's the reaction inside a glow stick, unpackaged, with enough material for five runs. Classrooms buy it. So do people who want one thing on the counter that's real chemistry.
A wooden kit that assembles into three spheres on gears: the Sun in the middle, the Earth going around it, the Moon going around the Earth. Turn the crank and you get the phases of the moon, a year, and a reasonable excuse for why eclipses don't happen every month. It's a school demonstration built for a desk, and it's the assembly that makes it stick.
A dodecahedron with an infinity mirror on every face, so each of the twelve sides opens into a tunnel of light that isn't there. RGBW LEDs, 258 patterns, and a music mode. It's a gaming-room object first, and it photographs far better than the price suggests.
Memobottle made it flat so it slides into a laptop sleeve or a bag pocket next to a notebook instead of rolling around the bottom. This is the A6, 12 ounces, Tritan plastic, freezer safe. It looks like a flask on a desk and a paperback in a bag. People who commute with a bag get it immediately.
Seven clear blocks, each with its own LED, that clip onto each other in any order. Only the arrangement decides the shape, so it's a different lamp every time somebody gets bored. Touch it to switch between seven colors. It's a night light that a kid can rebuild, and a desk lamp for an adult who never stopped.
Bluestar is the luminol that forensic teams actually use, and this is the training version: eight tablets, dissolve in water, spray, and old blood glows blue-white without total darkness. It is sold to labs and students. Where you point it in your own house is between you and your conscience.
Two parabolic mirrors face each other with a hole in the top. Drop the little frog in and an image of it appears in the opening, solid to the eye until your finger goes straight through. It's an old optics trick, 6 inches across, and it comes with the frog and a red ball to start. Anything small enough to fit works next.
A syringe of Panellus stipticus culture, a wood-rotting mushroom that glows faint green in the dark. You'll need a substrate, patience, and a very dark room; it's dim, and the photos online are long exposures. This is a real cultivation project, not a novelty. For someone who already grows things.
A small Bluetooth speaker with a sealed vial of ferrofluid in front, and an electromagnet that makes the black liquid jump and spike in time with the music. Four colors of backlight. The sound is a single 5-watt driver, so this is a visual product first. Nobody's buying it for the audio.
Walk within 10 feet and the owl says something. Over 360 clips are built in: dad jokes, sound effects, animal noises. No app, no Bluetooth, no pairing. Put it in a hallway, a bathroom, or the corner of a shop and it will ambush everybody with the same enthusiasm. Whether it's charming depends on how many times you've passed it today.
A xenon-filled glass sphere sits inside a coil. Feed it music and the plasma inside dances to it, glowing rings that pulse with the bass. The seller's warnings are extensive: high voltage in the driver, a strong magnetic field, keep pacemakers away. It's lab equipment that plays music. Treat it that way.
A spiral mesh printed over a white background, and the pattern shifts as you walk past it, a moiré effect that works in daylight without batteries. Twelve inches, hangs on a wall or stands on a shelf. It's a trick of geometry rather than electronics, so there's nothing to charge.
Seven inches of goose with a magnet in its beak, standing on a base on your desk, holding your keys and your clips and whatever else is steel. Anyone who's played the game about the goose gets it immediately. Anyone who hasn't will just think you like geese.
LEDs bounce between two mirrors so the light appears to recede into a tunnel that isn't there, several feet of depth inside an object a couple of inches thick. USB powered. The effect is optical rather than a trick you can learn past, so it lands every time.