Free Checked Bag with a Delta SkyMiles Credit Card

Checked luggage
 

If you have a SkyMiles Credit Card from American Express,  you can check your first bag free starting on June 1, 2010.

Gold, Platinum, or Reserve card holders will will automatically receive a first checked bag fee waiver upon check-in for all Delta and Delta Connection flights. Up to eight travel companions within a reservation receive this perk.

This will allow you to save up to $50 on a round-trip ticket or $200 for a family of four.