A motor drive for Tulio's most excellent Marble Machine #3. https://www.thingiverse.com/thing:1385312
Just take of the top finger spinner and this piece drops in. Drop the finger spinner back in and you are back to manual operation.
Software supports continuous and one-shot operation. (software upload coming soon...)
Thanks Tulio, you are a true artist!
28BYJ-48 stepper motor
ULN2003 stepper controller breakout board
This is a great combo for small projects... you can get a set of 5 motors and 5 controllers including cables for less than $15 at Amazon.