I was going through my backups today, looking for an old document. And I was surprise to find the first version of The Clock.  
I launched it, and was surprise that it was still working, after so many years, after so many new releases of OS X.  
I open the preference panel, … oh boy! What a long way from this to the today new version 3.  
So I thought, let’s try to find the different versions and see the evolution in time…

Going from a version with almost no feature, to a full featured app today. But always following the style of OS X.