Robots
Local robot stuff
Junun - Mark III and MegaBitty goodness
Discover This - Oregon-based store with robots and other educational products
Hobby Robotics
Non-local robot stuff
The Robot Store
LYNXMotion Robot Kits
Arrick Robotics
Robix RCS-6 Construction Set
Pocket Bot
Mobile Robots
Mr Robot.
Mekatronics
Majosoft - Engraving machines
Evolution Robots - Linux based kit
Living Creatures - Intelligent robots
Machine Grid - A Robotics portal featuring tutorials, autonomous robots, fire Fighting robots, Microcontroller [PIC16F84 and the Motorolla 68HC11] based robots and links.
Used-robots - Industrial arm robots
Acroname, Inc - Robotic specialists
Kronos Robotics
Tower Hobbies - Servos and more
Futaba, Corp - R/C servo manufacturer
Serv-O-Link Corp - Inexpensive gears, chain and sprockets
TechMax - Motors, bearings
Servo City - Well-stocked servo supplier
Balsa Products - Low cost servo supplier
Winfred M. Berg, Inc. - Gears, belts, couplings.
Small Parts, Inc - Hundreds of small mechanical components
Herbach and Rademan - DC motors, power supplies, batteries.
Micro Mark - Small tools specialists
International Frequency Sensor Association - Good source for sensor information