There are many great blogs out there in the web, especially related to postcard collecting. But this blog (http://eyescard.blogspot.com/) by Alexander Karmanovsky is quite interesting. He had a great idea: eyescards. You take a picture of your (or someone else's) eyes, add what ever you want (words, embelishments or nothing at all) and send it to the address written in the blog.
So, take a look at it and be creative! Remember: the eyes are the windows to the soul.