If you've never heard of Snafu Cards, they sell humorous greeting cards with a personal touch. You can see the sort of card ideas they're looking for at SnafuCards.com. Send up to 12 ideas at a time, by either mail or email. They'll only respond if they want to buy something, but their guidelines state that if you don't hear anything within two months, you should consider your ideas rejected. (Though they say it in a nicer way.) Snafu pays on acceptance -- $100 for all rights.