Arduino: Recommended Parts

hobby servo
T-Pro Mini Servo SG-90 9G Servo
http://www.hobbypartz.com/topromisesg9.html

relay
jameco

darlington array for stepper motor control
uln2003
jameco

stepper motor

1. Generic
   1. Breadboard
      1. Solderless + appropriate wire jumpers
      2. wood, nails, alligator clip jumpers
2. Basic Input and Output
   1. Digital Output: LED and resistor,  300 Ohms – 1K Ohm
   2. Digital Input: Resistor pullup (10K Ohm), wire switch
   3. Analog Input: Photoresistor, 100K Ohm – 400K Ohm  resistor
   4. Analog Output: LED and resistor,  300 Ohms – 1K Ohm
3. Using a transistor to control loads
   1. Transistor, LED, 5VDC: 2n7000, LED, resistor
   2. Transistor, LED, different power: 2n7000, LED, resistor, 9V battery or other power supply
   3. Transistor, motor: 2N7000,  motor e.g. Jameco 2081895, 9-15V, 47mA no load, 500mA normal, 9V battery or other power supply
   4. Transistor, RFP12N10L, bigger motor : 2N7000,  motor up to 12A, 9V battery or other power supply

Switch and pull up/pull down resistors
potentiometer? seems an important concept
Relay! what’s cheap? and what’s a good demonstration? reed relay to hack remote controlled outlet?
any other inexpensive sensors?