I found this link in my bookmarks. It quite a neat idea.
“What in heaven is a digital sundial?” That was the title of an article in Scientific American (August 1991), which prompted a flurry of mental activity in many a smart brain. One answer is on display here: a sundial that displays the time, not by throwing a shadow on a set of lines, but in plainly readable digits. The dial functions from 8:00 to 5.55ï¿½hr, in 5ï¿½minute steps. There is a smooth transition from one reading to the next.
Nifty! Santa, you reading this?