This is a very simple but useful project, strobe navigation lights for rc airplanes, or you can adjust the flashing time and make it a warning light for a forklift or even a turn signal light for a ...

In this project, I'll make a small circuit capable of blinking lights, on its output we get a digital signal that we can use to turn on and off an external light like an led or relay for bigger loads.

It is a pretty common first project to use an Arduino (or similar) to blink an LED. Which, of course, brings taunts of: you could have used a 555! You can, of course, also use any sort of oscillator, ...