As said its a workaround if you want a workaround. Another option is to use the Ethernetshield and get connected to an internet time server (S)NTP. If you know the average roundtrip time you can get (I guess) approx 10 msec accuracy. You just need an NTP server near you with the shortest turnaround time
Could you tell more about your metric clock concept?
How many hours per day, minutes per hour? seconds per minute? metric assumes multiple factor 10 => 100.000 seconds a day?
Hmmm... good thought, but that would definitely add a lot of cost and complexity. Will keep it in mind though.
As for the metric clock, it's actually a concept that's been around for a while (late 1700s actually).
I've always understood the concept to be as follows:
10 hours per day (full standard 24 hour period)
100 minutes per hour
100 seconds per minute
10,000 seconds per hour
1,000 minutes per day.
Now, you obviously can't just cram 100 seconds in a minute without redefining the timespan of 1 second. So, under metric time, are the following conversions:
1 metric second = 0.864 seconds
1 metric minute = 1.44 minutes
1 metric hour = 2.4 hours
Which is how you can span 10 metric hours over the course of a 24 hour day.
Originally, when the metric measurement system was adopted, many people tried to get the world to switch to metric time, but it just didn't stick.
You will still see references to it though... mainly in Sci-Fi. My favorite is in the 1927 film "Metropolis", where all the clocks show only 10 hours... I guess the point was that it was the future and they were more advanced, so they had adopted the metric system for everything.
I would definitely not be the first person to create a metric clock, however. I actually got the idea from a metric watch made by Swatch that I came across years ago. I mostly just want to do it for the hell of it... and because, while they exist, metric clocks are very hard to find. Or at least true metric clocks... you can often find analog clocks with the face replaced to only show 10 hours... but the clock hands still move based on the 12 hour analog system, so it merely crams 12 hours into a 10 hour scale.