Phidgets are a set of building blocks for USB sensing and controlling from your computer. Phidgets offer a variety of tools like touch sensors, temperature sensors, motion sensors, sound sensors, a variety of motors, switches, LCD displays, LEDs and lots more. They are ideal for interactive installations and interfaces.
Use the Phidgets Libraries and Drivers to start a project.
For an example, see the map-tracing robot by Stacey Devlin as an example of how to use MAX6 with Phidgets.