I made ScratchShield; a shield for Arduino or Shrimp (an Arduino Uno-derivative, see http://shrimping.it).

You can find the sketch and the corresponding stripboard schematic on GitHub.

This shield fits on the Shrimp-layout I designed. This layout (stripboard and PCB) will soon be available on my blog.

The Arduino-sketch is licensed under GPL v2.
The stripboard layout and underlying schematic under CC BY-NC-SA.

Please let me know if you make one (or two, or three, or ….)

Pictures:
pic.twitter.com/FlFCzPAdOq
pic.twitter.com/40Je4zjAz2