The seriously cool Lili Lite from Studio Smeets Design is a reading light, bookmark and bookshelf all in one. To turn off the light, you must put your book over the 'bookmark' as shown in the picture to engage a sensor. When you lift the book off, the light will come back on again. Available at lili lite for 99 euro, but--you know what I'm thinkin'--something similar would be DIYable, sensor and all. The only tricky bit would be to find a triangular-shaped light. (I love the 'mine & yours' pic on lili lite's website.) Via.