When you're old you have to do stuff on your birthday that you might not want to do. I was prepared for this at an early age thanks to my Norwegian mother. (I could not fathom the idea of taking the day off school to have a "me" day with mom, because it would be inexcusable to take a day off of anything unless you were deathly ill.)
When I was little, the coolest thing about my birthday was that it MIGHT be on Easter. (It never was; Easter has fallen on 4/20 in 1919, 1924, 1930 and not again until just 9 years ago, 2003.)
When I was an angst-ridden teen, the coolest thing about my birthday is that I shared it with an evil dictator (not that I thought Hitler was cool).
In college, the coolest thing about my birthday was that it was 420 (although that is wasted --haha-- on me).
I'm in the doldrums of coolness now. I suppose the coolest thing about my birthday now, is that I share it with Internet sensation George Takei.
Soon, the coolest thing about my birthday will be that I'm still around to celebrate it. :)