Veterans from Yahoo, DoubleClick, Epiphany and Salesforce.com have launched a start-up called Rocket Fuel that will use Internet users' past behavior to serve ads across the web. The company calls it an "intelligent ad serving platform that drives results for advertisers by automatically leveraging massive amounts of internal and third-party data and serving only the best impressions in the context of each advertiser’s unique marketing objectives."

"The Rocket Fuel platform goes beyond behavioral, contextual or geo-targeting by combining data mining algorithms, artificial intelligence and expert analysis to customize every campaign and drive results for advertisers. Using its real-time Progressive Optimization technique, Rocket Fuel is able to use rapid automated testing and user-level targeting to adjust campaigns around the clock, boosting campaign performance in hours instead of the weeks or even months it would take to pour through the data manually."

Rocket Fuel is a privately-held company with venture capital funding.