Anna The Red is the greatest Bento artist I have come across on the web. She's so highly regarded she even did an ad for Google. Check it out:
For those of you who don't know, Bento is a "single-portion takeout or home-packed meal common in Japanese cuisine". When bento is arranged in an elaborate style (such as people, animals, characters, plants, etc.) it is referred to as kyaraben or charaben (a shortened version of character bento).
Bentos are always edible, and created with all sorts of different foods. Creativity and true artistry are key. Let's just say the best bentos truly transcend the material (in this case, the material being food).
Anna's Bento Factory is full of images of her work, and best of all, incredible step-by-step tutorials. If you're interested in diving into the world of Bento, check out Anna's How-To section. If you prefer video to text, I'm a fan of this How-To by Cooking With Dog.
Anna's incredible work from her flickr page: