To the extent that consciousness is useful, it is useful in small quantities, and for very particular kinds of tasks. It's easy to understand why you would not want to be consciously aware of the intricacies of your muscle movement, but this can be less intuitive when applied to your perceptions, thoughts, and beliefs, which are also final products of the activity of billions of nerve cells.
In September, 2009, Sum became the number 2 book in the United Kingdom on Amazon's bestseller list, only behind Dan Brown's Lost Symbol.
SUM at the Royal Opera House
SUM has been turned into an opera at the Royal Opera House in London (Composer: Max Richter, Director: Wayne McGregor). The London Evening Standard hails the opera as "immersive, meditative and sweetly fascinating". Read about the background of the collaboration in Wired.