Greg Mankiw's list has a list of suggested readings for an economics undergraduate that are
fun enough that you would not be embarrassed (well, not too embarrassed) reading them at the beach
I have no quarrel with his suggestions of A Random Walk Down Wall Street, The Worldly Philosophers, or Capitalism and Freedom, all of which were available when I was an undergraduate.
But I don't think any of the recent books on his list are in that class. I particularly dislike Nalebuff, although the book Greg recommends from him is not the one I read.
I'm not sure I can do any better with books written since the 1970's, but offhand these would be my recommendations.
Perry Mehrling, Fischer Black and the Revolutionary Idea of Finance
William Easterly, The White Man's Burden
Tim Harford, The Undercover Economist
Bryan Burrough and John Helyar, Barbarians at the Gate: The Fall of RJR Nabisco
Daniel Pink, Free Agent Nation
Robert Kaplan, Eastward to Tartary
Bjorn Lomborg, The Skeptical Environmentalist
Alan Blinder, Hard Heads, Soft Hearts
David Warsh, Knowledge and the Wealth of Nations
I have just started the Warsh book, so I reserve the right to retract that recommendation. So far, he makes economics seem much more melodramatic than it really is, particularly the annual convention of the American Economics Association, the importance of which he seems to over-rate, in my view.
But anyone whose idea of good beach reading is economics is probably not an especially fun person as far as most people are concerned. I plead guilty.