Handkerchief "Save the Date" cards over at borrowed turquoise.
Handkerchief bunting by Little Birdie Secrets.
Amy over at Eat Drink Chic has designed some letter-writing paper sheets in the style of vintage hankies. I love her idea of using them as "Love Letters for the Newlyweds", an alternative to a wedding guestbook. They are beautifully designed and can be used for tons of other projects.
You can download Amy's hanky templates here at Eat Drink Chic.