Programmable color LED array from Evil Mad Scientist Laboratories. Our evil pals over at Evil Mad Scientist Laboratories have a neat demo video of their Peggy 2 Light Emitting Pegboard kit that they've populated with red, green, blue, and white LEDs.
One thing worth noting (and that we demo in the video) is that you can diffuse the big RGBW pixels into one continuous full-color display by placing a thin diffusing plastic layer above the LEDs-- it really works well. (The Peggy 2 just so happens to be the cover star of MAKE Vol. 18.) The Embarrassingly Easy Case Mod. The problem with basic electronics projects is that they have a very bad ratio of effort to result.
OK, you've got to learn to solder somehow. But the niftiest thing you're likely to end up when you've worked your way through the whole Let's Learn About Wires kit series is a weeny FM transmitter. So here, for your delectation, is a Thing You Can Make that's easier than that very first Two LED Flasher kit, and creates a genuinely cool (though not, I grant you, especially useful) effect. You've probably seen little LED lights of various kinds that cycle through red, green and blue, and then numerous psychedelic combinations of those colours.
LED Cube 8x8x8. At first glance this project might seem like an overly complex and daunting task.
However, we are dealing with digital electronics here, so everything is either on or off! I've been doing electronics for a long time, and for years i struggled with analog circuits. The analog circuits failed over half the time even if i followed instructions. One resistor or capacitor with a slightly wrong value, and the circuit doesn't work. LED cube 8x8x8 demo