This Google search (essentially, "find me any page")
or | -or +*
returns around 25 billion results.
Ryan Levering and Michal Cutler at Binghamton University estimated the average web page size at around 130 K. So we get a figure of around 130K x 25,000,000,000 = 3 petabytes (in round numbers) which might hide around 1.5 or more exabytes of unindexed data.
This website gives an idea of some methods used to estimate the size of the Web.
http://www.worldwidewebsize.com/