The Kiva gift card is already a savvy gift in itself — you can start with donations as low as $25. The money will go towards entrepreneurs who just need a little kick-start to climb their way out of poverty. Further, Groupon and Kiva are having a special deal in which you can buy the $25 worth of Kiva credit for just $15.
If money is a bit too tight for you, and if you still want to help the microfinance institution out, why don't you tell the world about Kiva. The company's website has a list of things you can do to spread to the world, which includes sending emails to people, handing out Kiva fliers and brochures, and putting banners on your websites.