I don't typically write about cases for the iPad and iPhone, but the Papernomad deserves special attention. These cushioned sleeves are wrapped in a patented paper that you're free to decorate with your own drawings, sketches, notes, writing... whatever.
Don't be put off but the word "paper." The outer layer is a special recipe that's tear-resistant, dries cleanly after getting wet and has less environmental impact than cotton products. I love the combination of high-tech and low-tech here.
There are sleeves for the iPhone, iPad mini, MacBook Air and MacBook Pro as well. Prices start around US$48.