Back in the old days, used this to build a DRO for the z-axis of a milling machine: http://www.nerdkits.com/videos/digital_calipers_dro/ http://www.nerdkits.com

Back in the old days, used this to build a DRO for the z-axis of a milling machine: http://www.nerdkits.com/videos/digital_calipers_dro/ http://www.nerdkits.com/videos/digital_calipers_dro/ And then got contacted by a blind mechanical engineering student who asked if we could make a set of talking (text-to-speech) digital calipers, which we did: http://www.nerdkits.com/videos/talking_calipers/ http://www.nerdkits.com/videos/talking_calipers/