Discover Card will match donations to the American Red Cross up to $500,000.
At the time of this post, it shows that "$63,885" has been matched so far so there is plenty of room left.
I tried to go back and find the link directly from the Discover Card website, but it disappeared. However, I found this link to the American Red Cross via Discover's link through facebook so I hope it works:
I know this is not a "slickdeal purchase", but if you're already planning to donate for a good cause then this would stretch your money further since Discover is matching. To me, that is a slickdeal. (But I apologize in advance if this post is viewed negatively from a SD perspective)