Here are a few ways to go about submitting the back side of your postcard, you know, the one with your writing on it ...
1. Send it to us in the mail. We'll scan it in.
2. Write on the back of an actual postcard. Take a picture of it (or scan it) and send it to us by e-mail. Then mail the paper postcard to someone you care about. Or to a stranger. Or us. Whatever.
3. Make your own. Just write something on note card or similarly rectangular piece of paper and take a picture of it.
Send electronic cards to firstname.lastname@example.org
Have fun, and be original.