If you're interested in what it takes to grow a business from 10 users to 10 million, you should check out this collection of Andrew Chen's most compelling writings on viral marketing. You'll learn how to conduct awesome A/B tests and how to find out exactly what your customers truly want from your product.ExcerptProduct design fact: A small number of features are used a lot, and most features are never used.This idea comes from one of my favorite books, Designing Interactions, where there's a ...