Magnificent: The Big Picture has a series of incredible pictures from the latest Soyuz and Shuttle missions to the International Space Station.
They are all amazing, but I think I like this one the best:
I know, it's not what you'd think I'd pick, is it? But it shows astronaut Soichi Noguchi in the station's cupola, taking one of his astonishing photographs that he posts on Twitter. Looking at this picture of him, and thinking of his incredible photos, really brings home the fact that humans are in space right now, circling the Earth over your head.