They were all the rage a couple years ago - but I have not seen them in a while. I've always liked them because the main part of the card is also a little gift.
In this one, the image is is Fall Leaves by Impression Obsession. I thought the shape really lent itself to a bookmark - so why not.
When the bookmark is placed over the card (or a page in a book) the magnets keep it in place.
To make the card, I just matted patterned paper over card stock on the front. Not positive about the competing patterns of the stamp image and the paper, but I was dying to use this patterned paper - so.... I did.