If you want books that give you powerful tools to wield for your benefit:
Life in Half a Second, by Michalewicz <--- suggestions to increase personal success
The Power of Habit, by Duhigg <--- how to make habit your servant
You Can Negotiate Anything, by Cohen <--- how to negotiate
How to Win Friends and Influence People, Carnegie
Drive, by Pink <--- what drives people in the age of creativity -- useful if you lead or manage people
Bold, by Diamandis and Kotler <--- new opportunities for business growth in the Internet age
The One-Sentence Persuasion Course, by Warren <--- very simple techniques for influence
Books that can make anyone a wiser voter and wiser judge of policies:
Basic Economics, by Sowell <--- if more people would take a handful of hours out of their lives to read it, the world would be better
Why Government Doesn't Work, by Browne
Freakonomics, by Levitt and Dubner <--- examples of applying reasoning and full analysis to various interesting cases
Broad topics in history:
A Short History of Nearly Everything, Bryson
Civilization, by Furguson
Why Nations Fail, by Acemoglu and Robinson
With the Old Breed, by Sledge <--- if people read one book on war, this should be the one
And one that is completely different:
The High Frontier, by O'Neill <--- human colonization of space