An effective strategy for generating new business leads involves targeting companies similar to current clients, particularly those in the same market or industry. Clearbit's Discovery API facilitates this process by using clustering algorithms to programmatically identify similar companies, which can enhance outbound marketing campaigns. By analyzing a list of existing customer domains, businesses can use tools like Ruby, Python, Node, or REST to search for and compile a list of competitor companies, as demonstrated in the document's example using Salesforce's competitors. This method not only streamlines the lead generation process but also creates a valuable list of potential sales targets, with Clearbit offering a trial Discovery plan that allows users to pull data on 200 companies for free.