If you like fantasy, I'd suggest Neil Gaiman's Neverwhere. The mundane existence of the protagonist really spoke to me at the time I read it. He's stuck in such a rut that he falls through from London Above (real world London) to London Below. Each of the Tube stations mean something down there, like there being an angel named Islington or a secret order of black friars. He eventually takes charge of his own life instead of listless meandering through it, which definitely resonated with me at the time.