Mother always taught us not to judge a book by its cover, but GalleyCat has uncovered two enormously distracting opportunities to break that rule.

Over at Bookninja, readers can judge a massive book cover mash-up contest. Sort through a library of re-imagined book covers, ranging from that mash-up of Cormac McCarthy and a parenting handbook to a science fiction version of a beatnik masterpiece. Go vote on your favorite.

Once your critical facilities are warmed up, go visit Judge A Book By Its Cover--an incredibly addictive site where you guess what Amazon rating a book received, based only on the book's cover. You deserve a break. Go play!