I have a book called 1 sentence. The Idea is that I get as many co writers as possible to write 1 sentence, then not write again until they see someone else write a sentence. (Basically make sure that you don't write two sentences in a row.) I'm not sure how good or tremendously awful this book will end up. It will be interesting to see.
Nothing ever came of it but it's still floating around on both of our profiles. Nothing really happens in it if I remember correctly; it's been a few years.
Anyone Interested?
http://www.penana.com/story/5474/one-sentence-story