Today is the last day that Estonians can make purchases with the kroon, their national currency that was introduced following independence in 1991. After today, they will have to use only the Euro for purchases.
There is a story about it today on NPR's All Things Considered.
I do have to say that you have to give props to a country which, after getting its independence back from Russia, put a picture on the 5 kroon note of the border between Russia and Estonia. There is a castle/fort on each side, and on the Estonian side, the sky is clear. On the Russian side, it is cloudy.
Just a coincidence, right? ;)