Acclivity today announced the acquisition of the MarketBlast product line from 4D, Inc. Acclivity will develop, distribute and support MarketBlast, auction management software designed to help eBay PowerSellers sell more, spend less and save time. The utility’s tools include listing creation, inventory management, customizable automation, contact and email management, and post-sales activities, including communication, feedback and fulfillment. MarketBlast requires Mac OS X 10.3 or later, and is priced at US$99.