Random #'s via serial port dongle?

This has probably been discussed before, but has anyone built a little device that amplifies the white noise from a transistor junction, and converts it into serial data?

As Tim mentions, lots of people have talked about doing this, but few actually have. Nevertheless, the device is still needed and no one has done it. I estimate you could sell 500 at $50 each within four months if there were PGP support for it. And I'll give you advertising space on the archive site. Real random numbers should be a standard part of every computer. Eric