The Lux Spectralis is a deluxe RGB (red, green and blue) LED (light emitting diode) blinky that you can build.
A small microcontroller (ATtiny13) is preprogrammed with many different fun display modes (pulse in/out, slowly changing between colors, etc) that you can select with the pushbutton.
Soldering is required. You will need a soldering iron, some solder and a pair of wire cutters to assemble the kit.
You will also need 3 AAA batteries.