depends on what crafts you might know. knitting a scarf and hat, baking some goodies, crochet house shoes, making pottery or ceramics, making a scrapbook of all the memories you two have shared-with hand written notes commenting on what a great time each was, photo album, embroidered handkerchiefs, a needlepoint picture, a rock garden for outside, a wreath for the door, a stuffed pillow for her bed, a meal she won't have to make, knitted handwarmers/leg warmers, a knitted headband, knitted socks, a crochet wrap/hand-loom pot holders, a painted picture, stationery with handmade paper, an afghan for the couch or bed, a prayer quilt, hand sewn sachets with her favorite scent for closets or drawers, hand sewn placemats or tablecloth.
If you have some crappy cookie sheets like ones that didn't make it through the first oven use cuz they're crap; take those and some wrapping paper. Cut out an exact shape to fit the inside and glue it to the inner surface. Then get some cute magnets, and when she opens it tell her to find a spot for her new magnet memo board! Yay.