WSJ - Oct 24 - A company called RapLeaf is building databases on people by tapping voter-registration files, shopping histories, social-networking activities and real estate records. RapLeaf ties people's email address to a profile about them. It uses that profile to target ads. However RapLeaf says it never discloses people's names to clients for online advertising. It has 1 billion e-mail addresses in its database and segments people into ~400 categories. Co-founded in 2006 by Mr. Hoffman, RapLeaf began as an online service letting people rate each other based on their business transactions. The company raised $1M in funding from investors including PayPal co-founder and Facebook investor Peter Thiel. The company closed a $15M fund-raising round this month. FULL ARTICLE @ WSJ