I talked to a writer who released some two free short stories at the same time as her first novel. (booksarecool.com)
Several authors offer free short stories / epilogues between books (Karen Chance, Kelley Armstrong, Elizabeth Hoyt), and it makes me keep coming back to the authors and reminds me to buy their next book. (dearauthor.com)
SK, same challenge here, but while we can't offer reduced prices, we can offer newsletter subscribers things like free short stories, either in the newsletter or by download, or access to subscriber - only giveaways. (writerunboxed.com)