A Leverage Engine is a tool that helps maximize the benefits of link building campaigns. There are four types of leverage engines: 1) Link Collector, 2) Content Pump, 3) Market Multiplier, 4) Index Driver. A Link Collector takes links and descriptions and converts them to RSS feeds. A Content Pump distributes articles and other content to websites for links. Leverage engines can identify link opportunities and distribute valuable content to build links and rankings.