Ralf Schwartz hat mich auf BookLamp.org hingewiesen, die einen interessanten Ansatz verfolgen:

BookLamp.org matches readers to books through an analysis of writing styles, similar to the way that Pandora.com matches music lovers to new music. Do you like Stephen King’s It, but thought it was too long? BookLamp allows you to find books with a similar level of tone, tense, perspective, action, description, and dialog – while at the same time allowing you to specify details like… half the length. It’s impervious to outside influences – like advertising – that impact socially driven recommendation systems, and isn’t reliant on a large user base to work. Take a look at the above video to see how we do it in detail.

Video (8 min.):