BonBonBon - A Toy Receipt Printer for Kids (and Grown-Ups)

My son is absolutely fascinated by the scales in the fruit and vegetable section at Kaufland - the ones that print those little stickers with prices and barcodes.
Watching numbers turn into a printed label feels like pure magic to him.

That fascination became the inspiration for a small DIY project.

I bought a cheap thermal printer, connected it to a Raspberry Pi, and added a simple USB numpad. The result is a tiny “checkout system” designed for a child’s room.

Here’s how it works:

• He can enter numbers using the numpad
• Press + and add them together step by step
• Press Enter to calculate the sum
• And out comes a receipt with the sum

Instead of prices, the receipt prints a random list of objects that could exist in a kid’s room - toys, books, mysterious items you’d definitely find under a bed.

The entire project is open source and written in Elixir.

(Now that I have a small thermal printer hooked up to a Raspberry Pi, my head is overflowing with ideas what else to do)