The Cauchy-Shwarz Master Class, is a pretty fun book and not bogged down with technical detail. Rather it is a ton of clever applications of this powerful inequality and its variants http://www.amazon.com/Cauchy-Schwarz-Master-Class-Introduction-Mathematical/dp/052154677X/ref=sr_1_1?ie=UTF8&qid=1415623270&sr=8-1&keywords=cauchy+schwarz
