[littlebird] posted a tutorial on making electronic dice.  He’s using an ATmega328 for the numbers work, and a mercury switch to activate it all. A nice blue enclosure to match the blue LEDs he’s using for the number display wraps it up nicely. Of course, someone had to mention that this was an amazing amount of over kill and it could just be done with a 555 timer like they used to do “back in the day”. [littlebird] responded with another tutorial to prove that he hadn’t forgotten how to work with the basics. He goes on to point out, now that we see both in action, that he can expand his microcontroller based one quickly with a few lines of code, where every new feature added to the 555 timer version would require additional components.

You can catch videos of both after the break.

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[David Williamson] has put together some pretty amazing little robots from bits of stuff he laying around the house. What initially caught our attention was this drawing robot over at HackedGadgets. We were impressed by the construction, as it looks like almost all of it was scrap. Upon clicking through the link we found a small collection that kept as amused for quite a while. Each one has some aspect that is surprising in its use of mundane materials. Need an omniwheel? Why not use plastic beads. Want a rail from which a robot can hang and drive? why not use drinking straws. Many of them may not have much for a brain, but the construction of the mechanisms is usually pretty interesting alone. You can see clips of some of his creations in the video after the break.

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[Daniel] wrote up a quick tutorial on interfacing with the MQ-3, or better known Breathalyzer from SparkFun with Arduino. While we would have used perhaps an op-amp/comparator based system and kept it in a much smaller package, the idea was so quick and simple and enjoyable we hoped an article might keep some hackers from drinking and driving.

[Thanks CletustheYokel for pointing out our silly category mistake.]

How many times has this one happened to you? Just coming home from work, you walk in from the garage, settle down, and pick up the newspaper. But wait, did you remember to shut the garage door?

Presenting the open garage door indicator. [xjc2010] chose the simplest circuit possible, using only a switch to turn on and off the setup, an LED acting as the signal, and a transformer/resistor combo to drop the voltage to an acceptable LED friendly 2.8 volts. We don’t like how he strung wire all over his house to place the beacon, and would have preferred something wireless in one way or another, but for under 6 bucks this gets the job done quickly and cheaply. Now if only we could get it to remind us if we turned off the oven while on vacation.

[thanks Craig]

GpsPasSion forum member [Ospray] has released a new version of MioPocket. For those of you that don’t know, MioPocket is a great unlock kit for GPS units. It basically unlocks the hidden potential of your GPS so you can access the built-in functionality of a PDA as well as retaining the GPS software. This means you can play music, watch video, play games, read and write office documents, and many other things with the once single-purpose device.

Originally written for Mio brand devices, it has been successfully used on a couple other brands. We’ve seen it on a Navigon 2100 using a modified install. This software can run directly off the SD card, so it can easily be updated or removed.

The fun part is fiddling with the scripts to get the newest releases to work on the Navigon and Magellan devices.

When I built my LumenLab projector, I used a thermal switch to run the fan. This simple control circuit looks like a nice alternative. The circuit is a simple adjustable temperature triggered Fet. If you know the resistance needed, you can replace the potentiometer with a cheap resistor. (You’ll want to use a DC fan)