How about arsenic for breakfast, lunch and dinner?
No one had thought that any living creature could live on a diet, but now NASA have discovered a microorganism on Earth that thrive by eating the deadly poison.
http://www.nasa.gov/home/hqnews/2010/dec/HQ_10-320_Toxic_Life.html
It increases the possibility for us to find life on other Planets with quite different conditions than on Earth.
how cool is that