"Are you ready to make some embedded projects with your Raspberry Pi? The Prototyping Pi Plate Kit fits right on top of your Raspberry Pi to give you plenty of prototyping goodness.
The Pi Plate features several goodies. It has a large prototyping area with "breadboard style" and "perfboard" style traces for chips, sensors, etc. Along the edges of the proto area, all the GPIO/I2C/SPI and power pins are broken out for easy connection. On the edges of the prototyping area, all of the breakout pins are connected to labeled 3.5mm screw-terminal blocks. This way you can semi-permanently attache wires, sensors, LEDs, etc. Finally, it has a SOIC surface mount chip breakout area just in case you need it."
For ordering details goto http://www.makershed.com/Prototyping_Pi_Plate_Kit_for_Raspberry_Pi_p/mkad53.htm
At least they didn't call it a "shield", like they do for Arduino :-)