Since the FIFA Championships are over down Brazil way, I guess there isn't much to do....
But seriously, let Paul enjoy finding that shortcut to change dates in the Taskbar System Clock.
This is about all I can find on the subject:
: to view all months inside the calendar date picker, just click on the current month name, and Windows 7 will show all months inside the calendar itself. And if you then click on the year at the top, you will see several years to choose from: in other words, from this simple calendar, you can change the date's day, month, or year - and a final click will show decades!
Source: Change the date on your computer (system clock + taskbar calendar in Windows 7)
The only use I've found for it is if I need to know what day was a particular date from 1900 to 2099.
MS seems tight lipped about revealing or explaining that shortcut.