Stack multiple plates, breakouts etc. onto your Raspberry Pi with Raspberry Pi Stacking Header - 2x13 Extra Tall. The female header part has extra spaces to make it 13.6mm tall: when placed on your Pi, a PCB will clear the Ethernet and USB jacks. The stacky pin part is also extra-long, 9.7mm, so that when a standard 1.5mm thickness PCB is installed, there will be 8mm remaining, plenty to plug into.
Adafruit Website: http://www.adafruit.com/products/1112