I don't like the idea of soliciting free contributions to a book... but I also don't agree that every work created in the community should be free. I like the idea of a Doom coffee table book and if @SLPerrin wants to write it and sell it, he should... there's nothing wrong with profiting from your work, even in a hobby community. My only objection is soliciting people to help write and then selling it. If he wanted to interview people, get statements ask them to fill out surveys or questionnaires that would appear in his book, I don't think there's anything wrong with that, either. Something just feels wrong about asking for contributors and then selling the work... especially since you'll need to start getting documents signed about what their compensation is if you're going to start selling something... you don't want them coming back later if the book makes a lot of money and demanding more because you're using their intellectual property.