Harold Thomas Finney II, a southern California coder, was Satoshi. He claimed to have received the first transaction from Satoshi just a few days after the genesis block. I think he sent the transaction to himself. Satoshi used a @gmx.com mail address. Finney was the very first person to post on the Sourceforge page of Bitcoin using a @gmx.com address. His vernacular and writing style are almost identical to the posts of Satoshi.
Finney knew in late 2009 that he was dying of ALS. The Satoshi persona was a necessary creation to remove him from the limelight. Bitcoin was too much for him to control while dealing with the onset of a terminal disease. He turned over the alert keys to Gavin Andresen and backed away from an active role in the development of his creation.
He knew his creation would never be trusted if most of the initially mined testing coins were ever to show up on the market so those coins were never spent. He may have intentionally disposed of the private keys to many of the addresses to ensure they would never hurt his brainchild. Some of the coins he mined in the beginning were used to pay for medical bills and cryogenic preservation of his body after his death. Those Satoshi addresses are as dead as Hal Finney.