Check out Cards for Causes. 20% of each card purchase goes towards the charity of your choice, and there's many to choose from. They have 2-3 delivery, so if you didn't get your cards out, you can still make it before Hanukkah is over ;)
Here's just two of their Chanukkah cards:
This is the link to the page you can choose your charities from: Cause Selection
Christmas? Go here.