iDroid:
CrossRoads:
atmega328, 16 mhz crystal, two 22pf caps, three 100nF caps.
14 resistors, 14 LEDs.Thanks, but isn't the the ATmega series quite large, compared to Attiny? ATtiny 40 seems to have a max 18 I/O pins and it's definetely smaller. Do I need the crystal and caps if I'll end up using this one? What about the program to turn the leds on, can you suggest anything "smoother" than a bunch of if - structures?
The smallest one with 14 pins would be an ATtiny4313.
PS: You don't really need the crystal, they work just fine with their internal clock. The only time you need an external crystal is when you need accurate timing for, eg. serial communications.
If you want a smaller AVR chip (Tiny84 or Tiny85) then you'll need an external 16 channel LED driver. I think the smallest 16 channel chip has 24 pins (eg. TLC5925).
iDroid:
Right, that's pretty obvious. I've got a friend who has an Uno, so I can program the chip with it, right?
You can do it that way So long as he doesn't mind you pulling it apart. The best way to work with bare chips is to get an "ISP Programmer". They cost about $12 and when you have one you don't lose any flash memory to bootloaders, etc.
PS: The ATtiny85 only really has five usable pins. You can use six pins but after you reconfigure the reset pin for I/O you can't upload any more software without a special device to configure it back again.