Fossilized bacteria found on meteorite
http://www.foxnews.com/scitech/2011/03/05/exclusive-nasa-scientists-claims-evidence-alien-life-meteorite/ - article (i know its fox news but whatever)
A scientist found fossilized bacteria on a meteorite. He concluded that "these fossilized bacteria are not Earthly contaminants but are the fossilized remains of living organisms which lived in the parent bodies of these meteors, e.g. comets, moons, and other astral bodies. The implications are that life is everywhere, and that life on Earth may have come from other planets." - summary via reddit
He theorizes that one of these meteorites could have hit the earth, and the bacteria on it could be responsible for the origin of life on our planet. This is a very bold claim, but it is an interesting theory.
What I admire most is that 100 experts and 5000 scientists have been invited to review the evidence and critique the paper prior to publication. Commentaries, both pro and con, will be published with the paper.