Just realized I shot the image being using on the cover of a book called Practical Arduino. I forgot all about it until I saw the book in SparkFun's break room.

Updated a few more things, recorded this video. As usual here is the source code.

Here is a compiled version for windows. This is untested.

A few more updates, added a few changes to MSAFluid to allow each snake to leave a different color particle trail.

Also changed the way snakes are controlled and how multiple serial controllers are handled.

The multiplier(block size) changes depending on how many people are playing.

Next on the list of fixes...changing multiplayer restart to allow for 1rst, 2nd, 3rd, 4th place.

I wrote this simple Processing sketch to illustrate how simple SparkFun's USB RFID Reader is to use.

The USB RFID Reader works with the ID-2, ID-12 and ID-20 RFID readers depending on how much range you need.

When an RFID is placed next to the reader it beeps and send the RFID's number via serial. If you have the Arduino software installed you can simply open up the serial monitor and see the RFID number.

This Processing sketch displays the product photo of the RFID being scanned...obviously this only works if you put the RFID number into the program, since every RFID number is different.

I've been working on a little snake game for Maker Faire. It's made in Processing using MSAFluid, Minim, OpenGL and is controllable via a Simon board or WiiMote.

Here is the source code for anyone who wants to check it out.

Connect an FTDI to the Simon board, reprogram it to send serial "1-4" for each of the buttons and use as a controller for Snake.

UPDATE:
Work a bit more on this today, made it a bit more 3d looking.

The serial side of things is commented out in this version. but you can use wasd and ijkl to control the players with your keyboard.

My little sister turned 21 recently, so I started working with the MQ-3 alcohol sensor from SparkFun to see if I could make a portable breathalyzer that runs off a 9v battery, can plug into to a computer via usb and that has some sort of indicator lights to show how drunk one might be.

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It has 6 LEDs which fade up in order depending on the level of alcohol it senses. I also can be plugged into a computer running a processing sketch that shows a more accurate fullscreen readout and displays 170 different images from the internet also depending on the drunk level.


Parts list:
Arduino Mini Pro (5v 16mhz version)
MQ-3 Alcohol Sensor
(2) Red LEDs
(2) Yellow LEDs
(2) Green LEDs
SPST switch
9v battery
9v battery connector
(3) 330k resistors
10k resistor
Right angle headers
FTDI USB->Arduino (5v version)
USB cord

The MQ-3 is a little strange, it definitely needs 5volts, much less and it won't function correctly. Because the sensor has a heating element it's values are easily skewed with hot or cold temperatures blowing on it. The MQ-3 has a burn in period of about 24 hours to give you accurate readings. Also I noticed that the MQ-3 alcohol sensor responds to a few other things like Rock Star energy drinks!

Other than the redundant pins the MQ-3 is pretty straight forward and easy to use. Simply hook up 5v to all 3 of the pins on one side, then hook up a ground (middle pin) and a 10k resistor to ground and finally the last pin goes to the Arduino's analog input. The pin with the 10k resistor to ground can be swapped with the pin going to the Arduino analog input.

The LEDs are taking up all of the PWM lines so they can be faded in sequence. Since the input from the MQ-3 sensor ranges from 0-1023, each LED covers a different range for example green1 covers 0-170 and green2 covers 170-340 and so on adding 170 each time.

There are also 170 images that are cycled through in the Processing sketch.