We’ve all been there: you’ve got a simple task you’d like to do with your microcontroller, and need an LED or ten to indicate that things are working correctly. You should use a current limiting resistor to keep from burning out LEDs prematurely, but this means selecting the proper resistor and soldering or breadboarding things into place. This is often neglected if you’re just doing a quick prototype, but it’s hard to shake that nagging feeling that you’ve broken the rules a bit.
For an easy solution to this tiny problem, seller Radomir Dopieralski offers the Rainbow Jellyfish Kit. This lovable design comes with a jellyfish shaped PCB “head,” which is adorned with LEDs in a variety of colors, along with the proper resistors and probe tentacles that hang down to plug into a breadboard.
While not explicitly advertised as such, it could make a nice learn-to-solder/SMD challenge device. It’s handy for its intended purpose, but it will also look nice adorning your garage or workspace, perhaps the end of a fan pull-cord!
