21. Invader

While most artists are preoccupied with getting their work in as many galleries as humanly possible, Space Invader is going above and beyond, literally. This year, not only did he take over the streets of Paris, Miami, Hong Kong, and the Alice Gallery in Brussels, but the mosaic artist sent one of his works into space and another to the bottom of the ocean on a sculpture by Jason deCaires Taylor. How can anyone top that?