Gone are the gluten free days of cardboard - y textures and strange flavors. (latortillafactory.com)
Put one of them in for free days and see what the sales impact would be on others? (janefriedman.com)
The only problem is there are about 300 of these sites and you should be posting your book free days on most of them for this strategy to be effective. (bookpublishingriches.com)