Probably no need to use assembler, no need to create a driver either (but /dev/coffee looks cool ). It's hooked up to the parallelport. Should be easy to create a simple program that will set one bit at a predefined time. I used to use a soldering iron quite frequently in the old days.. Made a simple 8 LED board for the parallelport once. This is basicly the same idea but instead of an LED you're driving a relay. The relay is able to switch the main power of the coffeemachine..

You can use this same trick to drive 8 (or even more; 256 in theory) relays. You could use it to switch the lights on/off in your house. Maybe hook up a light sensor so the light automaticly switches on when it gets dark.. Or voice activated... Or... Ahh... Now where did I put that soldering iron and that piece of breadboard??