Gyroc was amazing at the time and is still spoken about in hushed tones in the UK HPR community. While it was using ADXL50 devices for acceleration, the main gyro was an entirely custom built mechanical rotating gyro, wish I still had some pictures of it. Now that's all on a single chip you hardly even notice on the board :) Some pictures of it are here http://ukrocketman.com/rocketry/gimbal.shtml