The Founders Fund has a raised a new $220 million fund, their second. They will invest in 15-to-20 early stage start-ups, they announced today. The four managing partners of FF include Peter Thiel, well known for his investment in Facebook and Sean Parker, who was involved with Facebook in the early phase of Palo Alto-based social network. Geni, Powerset, Quantcast, and Slide are some of their other investments.