The Annals of Improbable Research tipped me off to Reto Schneider's Das Buch der verrückten Experimente (The Book of Weird Experiments in English), a collection of descriptions of one hundred scientific experiments throughout the course of history. As you might expect from the title, the experiments are all somewhat strange, yet nevertheless fascinating.
For example, how do cats always manage to land on their feet? Newton's laws would say that it's impossible:
The problem is that a falling cat has nothing to push against. Each turn that it makes with its forequarters causes its hindquarters to turn in the opposite direction. A half-clockwise turn in front means a half-counterclockwise turn behind. Theoretically, the cat should land all twisted up, which obviously is not the case.
Despite the tease of English-language excerpts, the book itself is available only in German. Unfortunately my German is not strong enough that I'd be able to read this book with very much success. (I can only just barely read Harry Potter und der Stein der Weisen without the aid of a dictionary.) But I'll at least add it to my list of "books I might be able to read someday".
[Updated 2pm to correct the English URL.]