Playable Games:
Indiegames web site
Play Adventure

Play Zork

Newgrounds - 50,000 mini games
Facade

molleindustria - political flash games

WTF?! - world of warcraft parody

Sketchfighter Alpha 4000

Super Columbine RPG

Info:

Arduino home - arduino.cc - look here for basic tutorials and other arduino related stuffs
Lady Ada
- lots good Arduino info, blog and stuff
Lady Ada’s Arduino Tutorial ~ Great intro, good to refer to if you forget something also
Hackaday
Hackzine
Make Magazine

Vendors:

Octopart - This site will search all vendors listed below plus more and populate the shopping carts for you!

New Electronics:
DigiKey
- components, etc
Jameco
- components, etc
Mouser
- components, etc
Sparkfun
- Arduino related electronics
Adafruit Industries - Awesome kits for arduino and hacking

Surplus Electronics+misc stuff (cheap!):
All Electronics - used misc electronics (local)
Alltronics - even cheaper than All Electronics…
The Electronic Goldmine
BG Micro - even cheaper than Alltronics
APEX Electronics - Awesome space junk yard
MPGA

Local Yokels:
FRYs Electronics - components, misc (local, bad service, good return policy )
All Electronics …
Radio Shack

Robotics:
Roboduino - Special arduino build for running multiple servos
Lynxmotion
- servos, servo controllers, robotics
Pololu - servos, servo controllers, robotics
Parallax - robotics, servo/motor controllers
ServoCity - has assorted parts and addons for working with servos (Servo Gear horns!)
Solarbotics - boutique robotics stuff, tini geared mototrs, custom gears etc = very very nice stuff - $$$

Misc Materials:
Mcmaster Carr - All strange forms of hardware and materials (fast delivery, has everything)

Specialty:
Happ Controls
- Arcade buttons, joysticks, coin trays, Vegas gaming stuff
Hagstrom Electronics
- Keyboard emulators
Velleman Kits - All types of handy electronic kits

Books:
Paul Shertz, Practical Electronics for Inventors (2006)
A very useful reference book - if your going to buy one general book on electronics - buy this one

Tom Igoe, Dan O’Sullivan , Physical Computing: Sensing and Controlling the Physical World with Computers (2004)
Great guide to putting microcontrollers to use - though a bit dated on the software side as its pre arduino code (basic stamp mostly)

Tom Igoe, Making Things Talk: Practical Methods for Connecting Physical Objects (2007)
An update to the book above (uses arduino instead of basic stamp) though does not replace it as the scope is much smaller of what is covered

Forest M. Mims III ,Electronic Sensor Circuits & Projects (2007)
Great little book on all types of sensors

John Iovine, Robots, Androids and Animatrons (2001)
Lotsa cool homebrew low-tech robotics tricks

 

Electro Mechanical Projects:
The Octopult

Daniel Rozen’s Wooden Mirrors

Mechanical Pong

Jon Haddock’s Automata

Mechanical Tetris