Save $50 on a Northwest Airlines booking

Deal of the day for Wednesday, March 26th, 2008- If you are planning to fly Northwest Airlines between April 1 and June 14, 2008, you can save $50 off of a booking of $250 or more. In a joint promotion with Paypal, the airline will refund $50 of this booking if paid for via Paypal, Ebay's on-line money exchange system.

To qualify, you'll also need to be a member of the airline's frequent flyer program, WorldPerks. There is no charge for this program, though. The refund will be credited to your Paypal account within 6-8 weeks. Tickets must be purchased in the U.S. through nwa.com.

Haven't used Paypal before? It's a very convenient service with a well-designed interface. I use it to buy from Ebay and Amazon, and collect freelance writing fees through it when the client declines to pay the invoice by mail. Paypal takes a pretty deep cut of my incoming money, though, so I prefer to use it only on purchases. Your account can be tied to a credit card or checking account.