Ganxy,the online service that allows authors and publishers to sell content direct or through other e-tailers, continues to add more features since its big push at this year’s Frankfurt Book Fair. Starting today, Ganxy users will be able to create a “showcase” with a photo of the book cover and copy that can be used across Twitter, Facebook, blogs, and online sites not just for a single title, but for a group of e-books that can be sold together in a single bundle.

Rather than combining multiple e-books in one large file, reformatting it, and creating a new cover image, with Ganxy, says cofounder Joshua Cohen, “sellers can create box sets of any e-books with just a couple of clicks.” Multiple books are bundled together, and can be quickly unbundled when a promotion ends. With this feature sellers can offer flash sales and change pricing in real time, as well as add or remove content.

Although Cohen declined to cite numbers, he did say that the number of people using Ganxy has “significantly gone up.” The service is free, but Ganxy takes a 10% commission on direct sales of titles through its service. Among the publishers using Ganxy are Diversion Books, Mercury Ink, OR Books, the Economist, and Wiley.