My dad sent me some postcards from the university he works at. They are made from 100% recycled materials, plus have seeds embedded in them. Needless to say, they are not very difficult to grow. Per the instructions, I soaked the postcard in water for a couple of hours, then laid it on some soil, and waited. I have a "new" postcard somewhere, but couldn't find it, so you can't see a great beforehand picture. The first picture is one I just started a couple days ago, and the second picture was from a couple weeks ago. You can still sort of see the design on the cards. I just moved offices, and the plants got banged up considerably in the move, but I have no doubt they will bounce back. I believe they are Marigolds, but someone else may be able to correct me if I am wrong.
This postcard is being used as the new "thank you" note, instead of wasting paper on letters and envelopes. It's one way to advertise the "green initiatives" that universities are working towards.