Here is an Arduino Arc Reactor I was for Halloween. It has a potentiometer that you turn to switch the mode of the LEDs from flicker, pulse, or solid. I used an Arduino to program the ATTiny85. Ones I finished it I ended up giving it to a friend. So I am not 100% sure on the capacitor’s values. Anything close to 450uF should be fine and depending on the power supply you may not need them at all.
– 2 resistors (10 Ohms hook to LEDs and 470 Ohms hooked to potentiometer)
– 10k Ohm Potentiometer
– LM7805C 5 volt regulator
– 2 small Capacitors (I think I used 450uF)
– ATTiny85 and 8-Pin IC socket
– PC Board terminal
– 8 white LEDs
– Round ProtoBoard
Arduino Code: Download
Adafruit Post: https://blog.adafruit.com/2014/04/07/attiny85-arc-reactor-project/
(07/19/2017) Update: The link on the Adafruit page is pointing to an old location on my site that no longer works.