A good way to burn Bitcoins. Most probably Satoshi will never ever move them.
edit: I'm wrong, see https://en.bitcoin.it/wiki/Genesis_block
But any other payment made to that address/pubkey are perfectly spendable by whomever has the matching private key.
Though that misunderstanding is somewhat common, so it's not impossible that the payee believed that they were sending the coins to an unspendable address.
I'm only aware Satoshi created Bitcoin and remained anonymous.
Block zero was in all likelihood "mined" by Satoshi. As a matter of fact, that specific block might even have been created by hand.
There's also the myth and legend of The Satoshi Wallet. People have software checking it automatically and _any_ transfers out would be stuff of legends immediately. Any major transfers would cause panic - the founder is leaving, what's happening?!