WhichBook is a web-based book suggestion engine. Unlike the site What Should I Read Next?, WhichBook doesn’t ask for a list of books you have already read. At WhichBook you use a series of sliders to indicate how much of a given element you want in your reading. Looking for funny happy sex? Peg the sliders for each to the maximum and see what WhichBook kicks out. Lists of books are generated and displayed on the right side of the screen for your browsing. For readers in the UK there is a “borrow” button in the upper corner which will link you into the public library system in the UK. Strangely the designers of the site seem to have missed out on an enormously profitable and useful feature: they could have easily linked the titles of the generated books into the Amazon.com system making it easier for people to read more about and buy the books. For another book recommendation service that uses writing styles as opposed to reading list comparison, check out BookLamp.