I love the idea of incorporating vintage postcards into your invitation design or wedding decor, or using them as save-the-dates or RSVP postcards. Choose ones that represent your wedding location, where you grew up, or where you're headed on your honeymoon. This could be especially fun for destination weddings! Check out CardCow.com for a selection of thousands of vintage postcards from all over the world. I could get lost exploring their site for hours!