I'm in... +1 by the way.
What makes me happy? That is a long list, but I think most of it comes down to awe and wonder. When someone sees something that truly strikes them with it. That look, that wide eyed look of amazement. Every time I see that it brings me such joy, be it from video games and seeing a new world to explore and enjoy, or from seeing the magnificence of looking out into the galaxy and getting a big dumb grin at how beautiful it looks. I know it probably sounds silly, but seeing others well up with excitement and happiness just makes me positively over the moon. :)