Anything by Upton Sinclair. A lot of people will argue for The Jungle, but King Coal spoke a lot to me once I found myself living in a company-run community for a time. Also, I'd argue the Socialist theme comes out like an after-thought in The Jungle, it's still an excellent novel, though.
Oil! just entered the public domain in the U.S. recently. It was the the basis for the movie There Will Be Blood
I can definitely identify with the meaningless job that one might feel is doing more harm than good for society. I suspect this can be partially attributed to the mentality of 'find a job, any job is better than being unemployed' -I'm still working through the solution myself but I'm inclined towards thinking that this could be a motivator towards finding work that contributes towards the betterment of society. Now, if only I could find some work like that, that actually contributes to a stronger sense of security like that described by Maslow's hierarchy.