Send Mail Get Mail - A postcard-sending website.
MyPostcard - Send real photo postcards and greeting cards - worldwide, from any place to anywhere.
The Simple Postcard - Text a photo to mail it as a postcard
Felt for iPhone - Handwritten cards for the modern world
NanaGram - Text your photos and we'll mail 4x6 prints to your Nana.
Fizzer - Send a personalised postcard with your photos. Holiday cards, thanks, greetings, invitations, birthdays and announcements.