DIY Mural
This article outlines how to paint your own mural using one of those handy-dandy mural kits and how much you'll save: 82% instead of hiring an artist to do it for you.
There are a lot of sites offering cheesy mural kits for kids' rooms. Here is one of the better ones I've seen:
http://www.rosenberryrooms.com/wall-mural-kits-for-nurseries.html