For those of you who don't keep up with such things but for some reason follow my blog (and yes I will have real content tonight and tomorrow) this is exceptionally fascinating.
NASA Discovers New Form of Life in a Lake in California
To summarize: NASA has discovered a microbe in Mono Lake California that substitutes one of the basic building blocks of life, phosphorus, for arsenic at a molecular level. This is something without precedent in nature.
To summarize further: The definition of what we would call life has just expanded, in a big way.
To summarize even further: HOLY SHIT!