Getting yourself started with Arduino

On of my cow orkers was interested in Arduino, and I'm a fanboy.   So when I got home, I put together a quick "dip your toes in" kit to lend him.  Roughly, it consisted of:

• Arduino Uno
• A-to-B usb cable
• two feet of jumper wire
• a mini breadboard
• a bunch of 10k resistors
• a half dozen LEDs
• sensors for flex, light, pressure and one I forgot
• two instant-on buttons, a potentiometer dial
• one miniature servo

So now he wants to know about good books to get started.  I think when I started, I was just fiddling with parts and relying on sample code on the Arduino site.  But since then I've read a couple of kewl books.  Try these:

• Getting Started with Arduino is very simple
• Programming for Interactivity is pretty hard-core

And of course, he wants a good starter kit.  I've tried two, and they're both great:

• Adafruit "budget" starter kit
• Sparkfun "flex" starter kit

Have fun!