There are three things I enjoy: getting something in the mail, anything free, something to do during naptime. Hippopost to the rescue! Their website allows you to pick a picture (upload one of your own or choose one of theirs), type out a message (up to 14 lines) and send it to anyone you want. They print and send it out. The catch? You choose an advertiser (they usually have one or two choices) that puts a little blurb at the bottom of your postcard.
We've used Hippopost to send out thank you cards, keep in touch with extended family members, and send birthday wishes from the kids' favorite toys. There are so many possibilities. We're even considering using the website to send out Christmas post cards this year. You can send up to ten postcards a day.