Arduberry for Raspberry Pi and Arduino Shields
The Arduberry connects to the Raspberry Pi (all versions) and allows you to use the hundreds of shields and sensors already available for the Arduino with the ease of writing programs for the Raspberry Pi in Python, Scratch and other higher level languages.
Raspberry Pi sold separately.
This board connects to the Raspberry Pi through the GPIO pins, and as you can see from the animation above, any number of shields and sensors can be added to it for more functionality.
Learn more about the Arduberry here.