I've read a few of these books now and every one has been bright and engaging and funny and has taught me loads. I can't recommend them highly enough. They're only small. Very manageable.
Have a look at the list of titles. Ten-to-one you find a load of subjects you think you'd be interested in. Twenty-to-one the book turns out to be more interesting than you expected. http://www.oup.co.uk/vsi