Spotting Emacs In The Wild

August 3, 2026 by Zoe Skyforest 26 Comments

Emacs is one of the big classic text editors, right up there next to vi. It’s famous for its interface and its ubiquity across the *nix world. It’s such a core piece of software in the coding world that it has showed up a fair few times in popular culture—and [Ian Y.E. Pan] has collated some of those appearances.

Emacs played a role in The Social Network, the retelling of the origin story of Facebook (the social network everybody used to use). Notably, Mark Zuckerberg used the tool to slap together a script for scraping a website. It also appears in Tron: Legacy, Arctic Blast, and the tech TV comedy Silicon Valley—more than once, in fact.

Other appearances include comics, Japanese anime series Key The Metal Idol, and a few miniseries and documentaries to boot.

[Ian]’s list is unlikely to be exhaustive. Both because he hasn’t seen every movie or TV show ever made, and because you can make new content featuring Emacs references tomorrow if you so desire. Still, it’s fun to see some of the famous properties that have featured good ol’ Emacs.

Don’t hesitate to let us know if you happen to put together a similar list about vi. The tipsline is waiting.

Easy Theremin Uses ESP32

August 2, 2026 by Zoe Skyforest 6 Comments

The Theremin is that classic electronic musical instrument that makes those weeee-ohhhhh noises which were so popular in mid-century science fiction movies. Mid-last-century, that is, because this century is just beginning. In any case, you could build one with old-school analog electronics, or you could go a more modern route, as [ericCycles] did.

The build relies almost entirely on an ESP32 microcontroller with minimal supporting circuitry. Like any other Theremin, pitch and volume are controlled by moving hands closer or farther away from two antenna. In this case, the ESP32 uses its capacitive touch circuitry to detect effectively detect hand proximity to the two antenna in question, and uses those values to control the pitch and volume of a synthesized waveform. That waveform is then pumped out over the onboard digital-to-analog converter for playback on external speakers.

If you want to build a simple Theremin-like instrument quickly and easily, it’s hard to beat the simplicity on offer here. We’ve featured some other fun variants over the years, too, like this version that uses time-of-flight sensors for the human interface.

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An Automated Water Tank Controller

August 2, 2026 by Zoe Skyforest 26 Comments

[Jumpor] lives in a part of India where the water infrastructure is a little frustrating to use. Water gets delivered to underground tanks outside of homes, and must then be regularly pumped into rooftop tanks prior to use inside the building. Typically, this pumping is handled manually—by switching on a pump and running it until water comes out of an overflow pipe to indicate the rooftop tank is full. [Jumpor] decided to improve this wasteful and time consuming process with a little automation project.

The build is based around an ESP32 microcontroller. It’s hooked up to an ultrasonic sensor which can measure the water level inside the rooftop water tank. When the sensor detects the level descending below a set point, the microcontroller fires a relay to trigger the lift pump to fill up the tank. Once the sensor detects the tank is full, the pump is shut off, saving liters of water compared to waiting for water to pour out of the overflow as an indicator of the same.

It’s a simple enough project, but [Jumpor] was sure to include the important practical considerations. Since the rig was being installed in a rental, it was desirable to not make any permanent modifications to the water system. Thus, a fresh cap for the water tank was modified to host the electronics and level sensor, such that the original could be replaced at a later date. Due consideration was also paid to things like avoiding crossing the minimum detection threshold of the sensor, which could lead to accidental overflows if not managed correctly.

The aim of this project was to ease the day to day burden of maintaining a basic utility. That’s the sort of project we love to see around these parts.

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Architectural LED Install Shows How To Do It With Style

August 2, 2026 by Zoe Skyforest 6 Comments

Anyone can string up some LED string lights in a space with mixed results. However, if you want to create a lighting environment that’s classy and stylish, it takes a little more finesse. [ipad.bendavid] has a great example of this, with a rather tidy architectural LED installation.

The final look is quite clean and evenly lit, without requiring the use of any diffuser material.

The electronic side of things is relatively straightforward. There’s an ESP32 running the show, commanding the colors for 928 individually-addressable WS2812 RGB LEDs. It uses the WebSocket API for real time control, integrates with Home Assistant, and even offers audio reactive lighting modes with the aid of an INMP441 I2S audio input module. A hefty 5 V, 60 A power supply ensures the LEDs are never short of juice. There was also careful attention paid to power distribution to avoid any dim spots or other issues.

Where it gets really cool, though, is the attention paid to the construction of the installation. The LED strips are installed in concentric square frames, which block light in specific areas to create a nice square pattern, with the LEDs facing the wall they’re installed on rather than projecting out to the viewer. This hides the strips themselves and eliminated the need for diffusers which can be a pain to get right.

Overall, the build is a pleasing one that plays with light and darkness and looks rather stylish in a way so many LED installs don’t. If you’re cooking up your own neat glowable projects, you know we’d love to see them on the tipsline.

Open Source Stream Deck Targets Flexibility

August 1, 2026 by Zoe Skyforest 6 Comments

Stream decks are very useful when you’re live on camera and you need to hit some complicated macro at a glance. However, there is sometimes a perception that commercial options are a touch expensive for what they are, an attitude which has spawned many DIY builds. [Fady Faheem] has developed just such a device of his own.

Named Stream32, the build is intended to be simple to understand and adapt to one’s own individual workflow. Putting one together is as easy as buying a display, hooking it up to an ESP32, flashing the firmware, and then adding pages of shortcuts as desired. [Fady] has designed the firmware to be flexible with regards to screen choice — currently, it can be set up for a 4″ Waveshare LCD or a nice roomy 10.1″ display from Elecrow. Since it’s open source, adapting to a wider range of displays is a potential exercise for the builder.

The great thing about custom stream decks is you have all the freedom in the world to customize them to your own specific setup. Play with the code, the functionality, the visual layout—all to suit your own needs. If you’re working on your own custom hardware, be sure to tell us on the tipsline.

A Compact Game Controller For Your Phone

August 1, 2026 by Zoe Skyforest 9 Comments

[Gil Yankovitch] noted that playing games on a touchscreen phone gave up a certain something in terms of the tactile feedback one gets from real buttons. To that end, he was inspired to build a controller specifically for phones that solved this very problem.

The result was JoyFon. It’s a small gamepad built around the Raspberry Pi Pico, and can be put together around an RP2040 or an RP2350 as desired. It has four face buttons, a directional pad, and start and select buttons, as well as additional shoulder buttons up top in later revisions.

The JoyFon enumerates as a standard USB HID gamepad, so you could use it to play games on just about any PC, laptop, or tablet. However, the JoyFon is specifically designed for use with smartphones in the vertical orientation. This guided the design of the 3D printed enclosure, which positions the USB-C port to plug into the base of a phone, such that the buttons sit neatly beneath it. It does cover some of the phone screen, but that’s not always a problem when playing emulated games with a 4:3 or similar aspect ratio. The result is a button and screen layout not dissimilar to that of the original Game Boy handhelds.

We’ve seen some other great custom controller builds over the years, like this fantastic design using keyswitches.

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Tiny Desktop Robot Has Radar

July 31, 2026 by Zoe Skyforest 5 Comments

One thing our futuristic world is largely lacking in is droids and robot companions and the like. [solitary dev] is helping to rectify that problem by building a little robot called TongDou.

As [solitary dev] tells it, TongDou is a “tiny open-source desktop gremlin.” An ESP32-S3 serves as TongDou’s brain, buried inside a tasteful brass chassis. An OLED display is TongDou’s face, and he uses a pair of wheels driven by gearmotors for locomotion. A speaker plays back pre-recorded voice lines, while a 24 GHz radar and an IMU enables TongDou to keep track of the space it’s moving through. They are publishing the design files on GitHub so other makers can build their own if so desired.

[solitary dev] hopes to develop TongDou into something to make a “workspace feel less dead.” It’s not dissimilar from the way studios used to use robots to liven up otherwise hackneyed movies and TV shows, and we could absolutely use some of that whimsy in the real world. We’ve featured other fun desktop companions before, too.

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