I used CTMH's Memory Game which comes with 24 - 3x3 chipboard cards in a sturdy box with a magnetic closure. I inked the edges, used Mod Podge to glue on the paper, stamped titles and a cut-out heart! I ordered the pictures already pre-sized from Scrapboookpictures.com* which was a great time-saver and let me zoom in and print only what I wanted.
*Unfortunately, I just found out that Scrapbookpictures.com has gone out of business as of January 3! They said that due to a struggling economy and tight competition they can't continue. For anyone that has ordered through them before, it is a big disappointment. I don't know of another company that offers the many different size options, the high quality and the customer service that they offered. I will really, really miss their business.