It's official:<p><i>MOSCOW, September 12 (Itar-Tass) -- Russian President Dmitry Medvedev has signed a decree instituting Programmer Day that will be marked on September 13 (the 256th day of a year) and September 12 in a leap year, the Kremlin press service said on Saturday.</i><p><a href="http://www.itar-tass.com/eng/level2.html?NewsID=14324034&PageNum=0" rel="nofollow">http://www.itar-tass.com/eng/level2.html?NewsID=14324034&...</a>
By that logic...<p>the 2nd,4th,8th,16th,32nd,64th,128th days<p>are all days of the programmer.<p>I guess we're just cool enough to get "sum(x +=x while x < 256)" days each year