'Success Kid' is a macro meme which features a picture of a baby with a pumped fist and look of unusual self-satisfaction. Folks started using the photo of 11-month-old Sam Griner -- which had been made available on Flickr -- as their Myspace avatars around 2008. But it didn't really hit its stride until 2011 when Reddit turned 'Success Kid' into meme that now has over 66,000 different versions.
Of course photo memes are actually people too, as we learned from the much-maligned Scumbag Steve. And Sam Griner, the person, happens to be starting kindergarten this very week.