Sheryl Sandberg, Facebook COO
How to wear it: Black power suit and a kicky necklace. How to scare them: Find some Facebook employees. Be really, really nice. Talk their ears off about your days in Washington and how you singlehandedly solved the Asian financial crisis, with a little help from Larry Summers and Bono. At the end of the conversation, take out a notepad and ask them for their names. Frown a little as you write them down. Next: