Arduino microcontroller board
I just launched into a new hobby that is cool enough that I thought some BT members might be interested. First off, Arduino is an open-source electronics platform that is taking the hobby world by a storm. In the old days, you could make your own electronics projects only by soldering circuits and wires together. Arduino makes it possible to make the same kinds of circuits and projects on what is called a "breadboard" (no soldering required) and control them using simple programming instructions downloaded from your computer.
Anyway, I just bought the Arduino starter kit ($80 from Amazon) which includes a bunch of diodes and wires and switches along with the Arduino Uno microcontroller. The book takes you through 15 simple projects that even newbies like me can grasp. Here's what Project 1 looks like. It really is just a simple circuit that uses the power from the Arduino Uno to a switch that, when pushed, lights up an LED light.
Push the button, the LED lights up. How cool is that? You can follow the path of electricity from the red wire on the Uno (left) over to the positive power bus on the white breadboard on the right. From there the electrons flow through the diode to the same strip that the pushbutton is on. When you push the button it closes the circuit. It jumps over the red jumper to the positive terminal of the LED and then down through the negative terminal across another jumper back to the negative power bus on the left of the breadboard.
More info here:https://www.arduino.cc/