A few days ago I stumbled upon the artist Amélie Dillemann while reading a magazine and was instantly enchanted! She does the most wonderful things using only (or at least mostly) cardboard: furniture, decorative elements like pictures and even clothes and accessories. You can view these artworks and more in her gallery:
Pretty amazing, aren't they? I really want to try using cardboard and a nice frame to create a diorama like hers (if I get around to it, I'll let you know about the outcome). It's a shame I'll never be able to create or buy shoes like the "Queen of France", though...