Real Ultimate Power: The Official Ninja Book
If I'm not mistaken, it references this website, which is a more humorous take on what ninjas are.
Now I'm worried ... I guess if you take ninjas seriously and believe in 'code of honour' and all that stuff, then you could be offended by this book and would rather prefer a book like this one. However, if you frequent that website and wonder about ninjas vs. pirates and how ninjas have sex and all that strange stuff, then I suppose a book like this might humour you.
I, for one, would keep an eye on this one and see how this book would turn out. The scary part would be hearing an audiobook version of this book. O_o