Selfish Gene is
hopelessly out of date with modern scientific findings on epigenetics (although, yes, it was a pretty eye-opening read for me in high school), and the snarky condescension of his more recent work is beyond my threshold for tolerance.
I first found out about him through my obsession with Douglas Adams, whom I'm convinced did far more in his short life as a layman to increase public appreciation for science via his fiction writing than Dawkins and his infuriating acolytes could hope to do.