Marking the 29th of February

I simply had to post something to mark this leap year, 29th February 2012, seeing as it doesn't occur very often. I don't think the day will be remembered for anything spectacular apart from encouraging news from North Korea and James Murdoch resigning as CEO of News International.
Sadly, Davy Jones of Monkees fame died today at the age of just 65, the victim of a heart attack.

This means nothing to me but there is an algorithm believe it or not to explain the occurrence of a leap year, as follows;

if year modulo 4 is 0
   then
       if year modulo 100 is 0
           then
               if year modulo 400 is 0
                   then
                       is_leap_year
               else
                   not_leap_year
       else
           is_leap_year
else
    not_leap_year