In 2010 NASA announced the discovery of microorganisms that, after being treated in laboratory, could keep growing only using arsenic, instead of the (though very small amount of) phosphate they also had in nature. However, this was confuted by further studies in the following two years. Has there been success in finding "alien" life on Earth, somewhere else, since then?
Edit: the NASA article from back then says what gilleain sais below. I naively hoped a couple of articles from different (not scientific, but not bad) journals were not modifying the facts. Thus the question actually is if non-carbon-based life has been found.