As a child, we played the memory game a lot. In fact, my brother was always really good at it and he and my little sister would play for hours.
I found this really cute idea for making your own memory game. She just used chip board, stamps, punches, and scrapbook paper and used modge podge to seal them all. You could probably use a heavy weight card stock instead of chip board.
The link to the picture is http://melissagoodsell.typepad.com/day_to_day/2008/11/memory-cards.html
Here are the pictures from her site. I think you could really have fun with this and do alphabets and numbers and all sorts of things.
She just punches out scrapbook paper with the scalloped square punch and then adheres it to the chip board.
You can also use stamps for fun images.