20 SF novels that will 'change your life'

"Spring equinox will be here in just a few weeks, and there's no better way to get ready for the seasonal change than to dig into some great science fiction books"
Actually I can think of several better ways to ready oneself for spring (like being outdoors) ... Still, an interesting list with some big favourites and some interesting omissions. And Sarah Canary spoilt for ambiguity.
Am only 50% qualified to judge though :)