Turn any pic into a postcard

Having been on vacation recently, I have a lot of pics I want to share with my friends. Thus, I have been thinking of some way to send out my pics to all my friends through postcards or greeting cards. That's when I came to know that it's possible to turn any image of artwork, vacation/ travel or photo image into a postcard or greeting card. What a godsend for me! Basically, any picture taken with a digital camera can become a postcard. So if you want to send a personalized postcard, do consider this option.