Eagle files for a DSP Shield to be used with Arduino Duemilanove and others.
It utilizes the Analog Devices ADAU1701 DSP IC. It also has solder pads for an EEPROM that can be used to store configurations and allow the ADAU to boot automatically when not connected to an Arduino.
Inputs and outputs are brought out to a pin header as I thought it would be more convenient than having TRS jacks directly on the board.