MichaelSmith writes: Scientists think that there might be arsenic based life in Mono Lake, California. If it shown to exist such life could have evolved independently from our own, or it could have forked from ours at a very early stage. Link to Original Source
The F-15 Eagle:
If it's up, we'll shoot it down. If it's down, we'll blow it up.
-- A McDonnel-Douglas ad from a few years ago