Hi all,
I've recently made this external to access the GPIO and the mcp3008 (or mcp3004) chip in the raspberry pi. They are standalone externals based on WiringPi (http://wiringpi.com/). Everything is in C so they should be reasonably fast.
To get the code, binaries and help files go to: http://nyu-waverlylabs.org/rpi-gpio/
All best,
J