A growing number of charities are inserting small change into their mail solicitations in hopes of making an impression on potential donors, after years of decline in the practice, says USA Today.

Who’s Mailing What, a service that tracks direct-mail operations, is finding more nonprofit groups including a coin in their solicitation this year as charities combat a recession-fueled drop in giving.

Ken Berger, head of Charity Navigator, said coin mailings generate a lot of frustration among people who comment on the watchdog’s Web site, but officials with the Leukemia & Lymphoma Society and Mothers Against Drunk Driving said their tests have shown a much higher rate of response when solicitations include coins.