Many math textbooks for liberal arts students emphasize real-world applications, but I am especially impressed with For All Practical Purposes: Mathematical Literacy in Today's World by Consortium for Mathematics and its Applications, W.H. Freeman. This book is over 1,000 pages (!) with about 25% devoted to voting and social choice and fairness and game theory. I was not aware that there are so many voting systems, and ways to deliberately manipulate a system by voting other than one's true preference. Fairness has applications in such things as business mergers, property settlement in divorces and inheritances, and organ transplant policies. In the settlement procedure of taking turns (one person selects an object, the other party selects one, the first party selects again, etc.), there are insincere strategies of not necessarily choosing the most favored object first when you know the preferences of the other party. I think students would enjoy these applications.