This made headlines last year when it first started getting media attention - basically some tech geeks had come up with a way of getting all of their required nutrients and calories through a liquid made directly of chemicals, with no actual food in it. Well, now it's hit the market:

http://soylent.me/

And there's an interesting article about the whole process here:

http://www.newyorker.com/reporting/2014/05/12/140512fa_fact_widdicombe?currentPage=all

Would you be intrigued to try it?