Perficient Inc. (Nasdaq: PRFT) has acquired Clear Task Inc., a company that provides Salesforce customizations for companies, for $7.9 million. San Francisco-based Clear Task implements Salesforce, the popular program used by companies  to track sales performance, and provide goals and feedback to employees. The deal gives Perficient a Salesforce consulting team. Perficient, headquartered in St. Louis, Mo., helps businesses use Internet-based technology for productivity, customer relationships, suppliers and reduce information technology costs.