I love the Wee Mobile cards and mobile from Wee Gallery.  They are adorable black and white designs on thick 5×7 cards that are perfect for babies developing vision.  There are many different designs and they can be turned into a mobile by attaching them to a Kikkerland mobile.  I used the mobile and Wee Gallery Jungle cards for my youngest daughter over her bed and she would stare are them for a very long time.  Every so often I would flip the cards over to change the picture.  With older babies you can use the cards as flashcards to teach them the names of the animals. There are 9 different sets you can choose from.

Check out the Wee Gallery site.  In addition to the cards and mobile they also have sweet wall decals, greeting cards, rubber stamps and more.  Their designs have a modern style that is very cute for babies and kids rooms.