Congratulations, you must have an address that someone found difficult to link to your real identity for them to be trying this trick.
They'll get dumped eventually as unconfirmed tx, but it'll take a while.
If you want to get rid of them faster, you can use the command line client to transfer your "real" BTC to another wallet. But if you pay tx fees that won't be worth it.
I suppose you could also very carefully construct transactions to transfer the 1-satoshi utxo's to the mining payout from block #1 or something. Back when 1-satoshi transactions were "normal" and actually confirmed occasionally, people would send satoshis to Satoshi that way. But with the current client they'll just disappear eventually.
How does it link my real identity at all?
I left them in a wallet, transferred all my bitcoins -minus these transactions, closed the old wallet (did it through sharedcoin transactions)
Can't find a single one of the sending addresses on my current address taint list?