I am building a music box that has 12 piano keys each on the top face and on two panels on the left and right faces that form a mini keyboard. When the correct sequence is played on the keyboard, a compartment on the front face will open. On the left face, under the panel, there will be a button that closes the compartment when pressed and a switch that allows you to switch between play mode, which enables free use of the keyboard, and unlock mode, which constantly checks for the correct password to be entered. On the front face, above the compartment, there will also be a screen that displays 4 different messages based on different events, including "Correct!", "Locked!", "Incorrect :(", "Play :3".
A to-do list that, as you complete it, goes through the life cycle of a butterfly, metamorphosing into a beautiful butterfly when you finish your to-do list!