My first choice is Suspects by David Thomson, first published in 1985 and now reissued. It's a unique work: it takes about 50 fascinating fictional characters from Hollywood films noirs and paints biographical sketches of them. So it profiles Harry Lime from The Third Man, Jake Gittes from Chinatown, Norma Desmond from Sunset Boulevard, Walker from Point Blank and so on. Each is a brilliantly written brief life going far beyond any celluloid existence.
Many of the suspects interconnect in a surreal series of imagined tales extrapolated from the movies. It brings some of the greatest screen figures alive in a fresh way. An ingenious book, and great for dipping into on short journeys.
The Cult of the Amateur by Andrew Keen is a polemic by an expert on the internet, who argues that the online explosion is undermining our culture and damaging our economy.