Novelist Sarah Maas wrote an epic tale with a big back story and she and her publisher Bloomsbury decided to use that extra material as part of an innovative marketing scheme. The material became four novellas that were published only in e-book form and released every other month, between January and July, for 99 cents each.
Each novella contains a teaser for the full-length novel, Throne of Glass, which is released this week. She is planning a sequel and will again use shorter ebooks to bridge the gap between that and the current book.
Maas already had a following from the online fiction community, FictionPress, but the release of these books built up interest in her work and increased her Facebook friends from 1000 to 6000.
If you're working on a book or other creative project that lends itself to this kind of strategy, it might be worth considering as a way to gradually build anticipation for its release.
(You'll find more marketing strategies in my book, "Marketing for Entrepreneurs"--and, yes, writers need to be entrepreneurs these deays--published by Pearson and available from Amazon and other booksellers.)