Giving your book away for free, either the first in a series on a permanent basis or a short term free book promo, is another way to get people to read you. (bookmarketingtools.com)
For some great info on them, check out Nicholas C. Rossis» blogpost on his results from using free book promo sites. (annerallen.com)
Experimented with free book promos to drive potential customers to books going through a Countdown Deal (stevescottsite.com)