Just recently I stopped to think about AVR's. There's something astounding about a chip that costs a couple of pounds and yet has a fully implemented processor, memory, flash, serial IO, ADC and reprogrammable ROM. Just think that's basically almost as powerful as an old 8 bit computer from the 80's in an 8 pin DIP package.
To put that in some perspective, the old 8 bits had countless support chips and their power requirements would be well in excess of any of the ATTINY range of Atmel's chips.
I guess that's why most car wiring looms are now serial loops with AVR support chips at the endpoints. In my project to build my own amplifier (see other blogs) I'll be using AVR chips for system control.