Satoshi Nakamoto
Satoshi Nakamoto is the founder of Bitcoin. He is said in a p2p foundation profile[1] that he is from Japan. Beyond that, not much is known about him.
Possible Motives
He left some clues about why he is doing this project when he include the following text in the Genesis block, "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks".