The Mammoth Encyclopedia of the Unsolved- Discusses TONS of random unsolved/mysteries of the world. Atlantis, Man in Iron Mask, Agatha Christie, etc. There's like 65 different chapters each with a focus. It's a fun read and pretty informative at time, the problem is that after about 3 chapters the author ignores being unbiased.
Initially the chapters discuss possible things that could have happened, and then gives evidence for an against. Later on though, the author decides that certain things are "fact," such as Poltergeists, Ghosts, Psychics, etc. This kind of kills half the chapters because his own silly views skew them. Lines like "There are too many eyewitness to even begin to ignore _________________" (Insert Loch Ness Monster, Ghosts, etc.)
That may have been plausible back in 2000 when he wrote the book, but in the age of cell phone cameras... shit that can get caught on camera WILL. 1000 people have eyewitness accounts of "seeing" the Loch Ness Monster, yet no one got a good picture? I'd wager that everyone who fucking goes to the Loch brings a camera, so wtf. More examples, but you all get the idea.
The chapters on the non paranormal are fun. Discussing a different Mona Lisa, Agatha Christie's insanity, who the Man in the Iron Mask might be, and so on is actually interesting, and I'll finish the book because of it. As for him criticizing scientists for not keeping an open mind about the paranormal. Meh, without a picture eyewitness accounts don't mean jack shit to me.