Check out the photos on the left. Next to the Harbour Master's office on a dock in the town of Harlingen, Netherlands, there's a working crane you can spin around. Better, you can rent it and drive it around all night. It's been converted to a hotel room. How could any former little boy resist?
That's my top find in a fun, nearly 300 page directory of strange places to stay from the web site Unusual and Unique Hotels of the World. I recommend you spend some time with it when you're not busy. You'll enjoy it.
Alongside a few tree houses and ice hotels (we'll have our own report from above the Arctic Circle in Lapland at the end of the year) and other offbeat places to stay, there's also a cave hotel in Cappadocia. But there's a destination I can speak of from my own experience, I can heartily recommend the Cappadocia Cave Suites. Extraordinary facility, gracious hospitality. Here's a couple of shots of our room: