If you have an American Express card, the company wants to give you five songs on iTunes for free. Just hit up this URL and enter your card information (we double-checked -- it's an official deal, not a scam), and then whenever you buy five songs on iTunes with the same card, you'll get refunded the price. Nice bonus for the weekend, if you happen to be an AmEx card holder. It's also an interesting way to get you to use your AmEx for iTunes purchases.
If you've been meaning to pick up The Beatles ever since their music finally appeared on the store, now's your chance. Enjoy!