We decided not to send Christmas cards and gifts to our business customers this year, and instead donated the money to Kiva and sent out an email telling everyone what we had done on their behalf. It worked really, really well. The feedback we're getting has been phenomenal and many people are interested in finding out more.
An additional benefit is that we were able to send it out to many more people than we would have sent gifts to. Overall, we emailed several thousand people in Australia & Asia and I'm hoping we've converted a few into Kiva givers! Obviously this is good for us as well - it gives our customers and people we're associated with a good idea of the values and ideals we hold dear.
Please steal our idea!

You could do this for friends and family as well as customers and suppliers.
Here's the Christmas email we sent -
http://emarketing.clearlightdigital.com/em/mail/view.php?id=738917556&k=16c3b05And here's the page where we're promoting Kiva on our website -
http://www.clearlightdigital.com/about/kiva.html