World's total CPU power: one human brain

"Lest we get too enamored with our technological prowess, however, the authors make some comparisons with biology. 'To put our findings in perspective, the 6.4*1018 instructions per second that human kind can carry out on its general-purpose computers in 2007 are in the same ballpark area as the maximum number of nerve impulses executed by one human brain per second,' they write."