At Home by Bill Bryson
This is the sort of usefully erudite books that tells you stuff you didn't know about ordinary things that you didn't know there was anything to know about. Every page should spark an idea from all but the most fanatic literary modernist. I particularly liked the deadliness of stairs, the shocking conclusion of the 1851 church survey in Britain(1) and the tangled history of the Great Exhibition.
City of Sin by Catherine Arnold
I haven't started this yet but I'm hoping it will set me off down the road to Southwark with the right amount of bear baiting, prostitution and substance abuse.
(1) It found that less than half the population had attended church at all and of those that did less than 20% went to an Anglican Church.