It may surprise some that five-year-old Polyvore is having its best year yet. The social design hub has seen its highest traffic ever this year, and will more than double its advertising revenue. Users love sharing their own “sets” of outfits or interiors. Advertisers love the data they get from Polyvore, which sends reports on the most popular brands. (The sets also funnel traffic to sites like Net-a-Porter and Neiman Marcus.) Lee is quick to credit much of Polyvore’s success to co-founder Pasha Sadri (now CTO), from whom she took the CEO title this year. Her first order of business was opening a New York office. The “infinite fashion magazine,” as Lee calls it, is only getting bigger from here. Her No. 1 cause: Get more women into computer science. –D.R.