How about giving them an Acre of Rainforest, or a cow, or a herd of chickens.....?? Of course you don't actually give them these gifts, but they are donated by charity on their behalf.
Try Googling World Land Trust for the Rainforest or Oxfam Unwrapped for other interesting gifts.
We recently celebrated our 40th wedding anniversary and specified No Presents, but somebody donated a batch of chickens on our behalf to an African Family via Oxfam Unwrapped, and we were delighted at the gesture.