Read an interesting article about the possibilities of life here and here, a new branch of microscopic life that uses arsenic instead of phosphorus as an essential element of its molecular structure, expanding the possiblies of where and how life may evolve. "We know that some microbes can breathe arsenic, but what we've found is a microbe doing something new - building parts of itself out of arsenic."
It's not 'shadow life' in the sense that it is still life that uses DNA and RNA, and not something completely different, but certainly encouraging nonetheless about what life will be found out there in the cosmos. I still wonder if we'll discover microbal life elsewhere in the Solar System in my life time. I hope so, I'd like to be around to see what happens when we do.