Computing with the command line

Here’s something we thought we would never see: computing with just pipes, /dev/zero, and /dev/null.

As a thought experiment, [Linus] imagined a null byte represented an electron. /dev/zero would have an infinite supply of electrons and /dev/null would make a wonderful positive power supply. With a very short program (named mosfet.c), [Linus] can use Linux pipes to control the … Read the rest

A talking reverse geocache puzzle box

Here’s a talking reverse geocache puzzle box which [Erv Plecter] built as a wedding gift for his friends. The box itself isn’t really the gift, but a surprise delivery system for a collection of cash from the couple’s circle of friends to go toward the honeymoon. We think this is about fifty times more fun that getting a fat envelope … Read the rest

Numerous quiz buttons built on the cheap

[Sprite_TM] was tapped to build a rather large quiz buzzer system. Judging from his past work we’re not surprised that he seemed to have no trouble fulfilling the request. As the system is not likely to be used again (or rarely if it is) he found a way to finish the project that was both quick and inexpensive.

Each … Read the rest

Simple machining process repairs broken control knob

[Francisco] is helping his mother with a repair to the headlight knob on her Ford Ranger. Above you can see the broken knob on the left, and what it is supposed to look like on the right (taken from [Francisco's] own vehicle for reference). We’ve encountered split shafts on plastic knobs before and decided it was not something that could … Read the rest

FPGA Snake game uses no VHDL at all

We’re really not supposed to start a feature like this; but this hack is awesome. It’s a game of Snake implemented by an FPGA dev board. It uses a 16×16 LED matrix as the display and an SNES controller for input. So far it sounds like a very normal version of the game. But as you start to hear … Read the rest

Tubular POV display

[Ryan]‘s cylinder POV display is an amazing piece of work. Right now it’s impressive sitting on his workbench, but we’re sure it would be astonishing hanging above the middle of a dance floor. There are 64 RGB LEDs on this display and they’re certainly bright enough to liven up any space.

Power is provided through a slip ring. The ground … Read the rest

DIY ultrasonic plastic welding

Here’s something that may be of interest to all the reprappers, vacuum formers, and other plastic fabbers out there: ultrasonic welding of plastics. If you’ve ever wanted to join two pieces of plastic without melting them together with acetone or screwing them together, [circuitguru] is your guy.

Ultrasonic welder setups are usually reserved for companies that don’t mind spending tens … Read the rest