there are many reasons you use a notebook: at work to take notes, at home to build a to do list or a sacred spot to share your most precious inner thoughts (aka a diary). Notebook manufacturer Magnus Ferreus has created "the worlds first emotion-stirring notebook".
The Notebook will make you cry as you write in it. The pages are coated with the same compound that causes you to cry when cutting onions (hence the name). The compounds are released as you write, they evaporate and cause you to shed some tears.
These notebooks will first launch in Japan. Prices and release date are still unknown.
Maybe this is all a hoax but you never know.
Source : http://onionnote.com/