A behind-the-scenes look at how tomorrow's hottest startups are being primed for greatness Investment firm Y Combinator is the most sought-after home for startups in Silicon Valley. Twice a year, it funds dozens of just-founded startups and provides three months of guidance from Paul Graham, YC's impresario, and his partners. Receiving an offer from YC creates the opportunity of a lifetime. Acclaimed journalist Randall Stross was granted unprecedented...