Any Dilbert book, not comic strip compilations. The Dilbert Principle, The Dilbert Future, The Joy of Work, Dilbert and the Way of the Weasel, and Dogbert's Top Secret Management Handbook.
It's 5 books long, so you'll have plenty to read... and aside from being funny, if you allow yourself to really think about it, there are a lot of existential questions.
And call me crazy, but I've read them all over 10 times and they've significantly changed my life.
Hithchikers Guide to the Galaxy is a bit of a childish read ( in terms of skill, not in terms of content ).
I advise anything by Nick Hornby - Fever Pitch ( football related, black humour ) and A Long Way Down ( hilarious, absolutely brilliant. About 4 suicidals who meet on top of Toppers Tower in London. Excellent read ).