Go to www.thebookseller.com, and scroll down. About two-thirds of the way down on the left is the voting box for their annual Diagram Prize - oddest book title of the year. This year's contenders:
The Changing World of Inflammatory Bowel Disease
Collectible Spoons of the 3rd Reich
Crocheting Adventures with Hyperbolic Planes
Governing Lethal Behavior in Autonomous Robots
What Kind of Bean is This Chihuahua?
Afterthoughts of a Worm Hunter
You want to run out and buy all of them, right? In fact, multiple copies, so you can give them to your friends, 'cause who could resist topics like that.
I voted for the spoons one.
You can find a list of previous winners on Widipedia. My favorites? 1995's Reusing Old Graves and 1979's The Madam as Entrepreneur: Career Management in House Prostitution. And to think I chose to work in publishing, when there was such an interesting alternative career path.