One of the PCB manufacturers I have been using as of late offer a feature on all orders where you can give permission for them to produce extra copies of your board in return for two randomly selected boards of similar size. Seeing as how the feature only costs an extra $0.10, it’s an interesting thing to try. I have started labelling all of my boards that I send off for fabrication with my address so people can find me here, and I will post schematics and parts lists so people can put them together. They’re all pretty simple circuits, but what do you expect for $0.10. Also I should point out that not all of these circuits work, and I will update this page as my prototypes come back as to whether the design is functional.