Charity Credit Cards
These sound like a good idea in principal - basically every time you spend a unit of currency a percentage of that money is donated to the charity. The charity will usually get a donation on you signing up as well.
The bad news is the cash backs are usually very small percentages which is bad news for the charity.
Also these charity cards tend to have very poor rates on them - so the card you receive isn't that good a deal for you.
You would be better off if you get a better cashback deal and then donate the money yourself to your chosen charity each year.