Mega variants

Are there other variants of the Mega/Due like this Ethermega from freetronics? http://www.freetronics.com/collections/all-products/products/ethermega-arduino-mega-2560-compatible-with-onboard-ethernet Am updating my screwshield design to make room for the ethernet connector. Are there any other variations I could make space allowances for at the same time?

I guess Mega ADK would make sense too, looks like ethernet connector is on the other side of the board http://www.adafruit.com/products/563

Or just 2 USB connectors? Both look like 4 pin device on the back side.