I'm developing a cryptographic daughter board for the BeagleBone Black
   [1][2]. The design goals are to provide a "hardware-api" when an
   embedded systems engineer has available to him a TPM, HWRNG, EEPROM,
   and some additional hardware implemented algorithms (with embedded key
   storage) all on one board. My vision for this board is to see it used
   on a BeagleBone and see someone make a cool crypto device like a USB
   powered wallet or an embedded network server.
   There is a small GoogleGroup [3] where we are discussing the
   requirements, secure boot options, and other details and I'd like to
   invite the community here to join the conversation or lurk and
   following along. If there are any Electronics Engineers, I'd especially
   appreciate your participation. I'm an embedded software guy, so while
   designing the PCB from scratch is a fun challenge and I could use some
   backup :)
   It's very much in the design phase at the moment, but I do have some
   components that I'm breadboarding. While some details are BeagleBone
   centric, I think any embedded device that supplied 3.3V and supports an
   I2C bus could use this board.
   Josh
   [1] [1]http://datko.net/cryptocape/
   [2] [2]http://beagleboard.org/Products/BeagleBone+Black/
   [3] [3]https://groups.google.com/forum/#!forum/cryptocape

References

   1. http://datko.net/cryptocape/
   2. http://beagleboard.org/Products/BeagleBone+Black/
   3. https://groups.google.com/forum/#!forum/cryptocape