Pramode C.E. writes – “With a low-cost, general-purpose microcontroller like the PIC16F628, bits and pieces of cheap, commonly available electronics components, and LOTS of code, you can build many interesting `toys’ and hook them up to your Linux machine – a really great learning experience for the hardware hacker who wants to learn Linux, or the Linux hacker who wants to learn a bit of hardware. This article describes how I went about building my temperature-sensing project – amateur Linux/hardware hackers might find some of the ideas useful when they start building things on their own.” Link.