Continuing my newfound interest in programmable hardware, my latest project has been to create a LEGO minifig equipped with an AVR microcontroller backpack. The chip on his back (which has more computing clout than a ZX81) is used to receive input from the light-sensitive resistor in his left hand, and control output to the LED in his right. This means that by waving your hand over the LDR, you can programme him to record around thirty seconds of blinking morse code.

Thanks go to Alex Weber for his very clear instructions and C source code which showed me how to create the circuit and programme the chip.