Here's the second half of the list of what I see being the 50 Essential SF novels you probably should read.
Arguments? Let's take this to Twitter.
Neuromancer, William Gibson (1984) Because without this, cyberpunk (such as it is) would be nothing, really.
The Handmaid's Tale, Margaret Atwood (1985) I prefer Oryx And Crake - I think Atwood only gets better and better - but I cannot deny that this is more essential. Still pertinent; still - maybe even more than it was - terrifying.
Blood Music, Greg Bear (1985) Where so much SF looks outward, this went back inside, small scale, with far-reaching consequences.
Watchmen, Alan Moore & Dave Gibbons (1986) Utterly essential. Where superheroes are past of the SF canon, so this fucks with them, presenting both the ultimate story, and the full-stop to it.
In The Country Of Last Things, Paul Auster (1987) The collapse of a future world told through the collapse of memories and language both.
Mindplayers, Pat Cadigan (1987) The psychological effects of a cyberpunk world; a great counterpoint to Neuromancer.
Hyperion, Dan Simmons (1989) What's not to love about taking the Canterbury Tales and adding spaceships and time travel and multiple framing narratives with their own distinct styles?
Use Of Weapons, Iain M. Banks (1990) The best Culture novel? Probably.
Snow Crash, Neal Stephenson (1992) If you're going to be ballsy enough to give a character that name, and then talk about your brain having a BIOS, you deserve to be read.
The Doomsday Book, Connie Willis (1992) Time travel + medieval weirdness + future viruses.
Red Mars, Kim Stanley Robinson (1993) Nobody does colonisation like KSR. At points, it feels like this could be what actually will happen.
Vurt, Jeff Noon (1993) Expect to feel pleasure. Knowledge is sexy. Expect to feel pain. Knowledge is torture.
Girl In Landscape, Jonathan Lethem (1998) Things I want to read about: genderless terraforming aliens; invisible pet deer; bizarre inter-species sexual tension. Ticks all three boxes.
Ark Baby, Liz Jensen (1999) The world becomes barren. People start breeding with monkeys. Satirical dystiopia shouldn't seem this effortless. (Also, it's Liz Jensen. More people need to read more Liz Jensen.)
Thy Kingdom Come, Simon Morden (2002) I had this on CD-ROM, back when The Internet was the future of literature. It was the best post-apocalyptic narrative I had ever read. Still right up there.
Black Hole, Charles Burns (2005) A PSA: Don't have unprotected sex unless you want to turn into a weird alien mutant.
Never Let Me Go, Kazuo Ishiguro (2005) I've seen arguments that this isn't SF. Bullshit. It's a near-perfect and devastatingly sad vision of an alternate life we might have had, were it not for our own morals regarding cloning.
Air, Geoff Ryman (2005) Take a tiny Chinese village. Give them a psychic version of the internet. Watch the results.
The Road, Cormac McCarthy (2006) Our world, destroyed. Some of the best writing I have read, or will ever read.
Glasshouse, Charles Stross (2006) A 27th century version of the Stanford Prison Experiment, and dealing with notions of the self in a way that few other books have.
The Yiddish Policeman's Union, Michael Chabon (2007) My favourite alternate history. Subtle, but far reaching. And it's funny! Actually funny!
Zoo City, Lauren Beukes (2010) Another one that causes SF-genre arguments. Another one where I couldn't give a damn: it's pretty much a perfect alt-future bit of brilliance.
Embassytown, China Mieville (2011) Again - I've said this before - you blend aliens and the concept of language, and I am entirely sold. That and, the writing in this novel is just extraordinarily good.
Jack Glass, Adam Roberts (2012) No less than three superb SF narratives wrapped up in three superb locked-room mystery stories. It feels like truly original writing, and it's rare to be able to say that.
Angelmaker, Nick Harkaway (2012) Gonzo, in every sense of the word. (Which is ironic, as it was Harkaway's previous novel that featured a character with that name.) SF-spy-fantasy-thriller brilliance.
And here's Ian's.