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The best sci-fi comedy ever
The Ultimate Hitchhiker's Guide: Five Complete Novels and One Story (Literary Classics - Gramercy Books)The Ultimate Hitchhiker's Guide: Five Complete Novels and One Story (Literary Classics - Gramercy Books) by Adams Douglas
Buy used from: £28.46
The original and best - all five fantastic books in one volume
Red Dwarf Omnibus: Infinity Welcomes Careful Drivers AND Better Than LifeRed Dwarf Omnibus: Infinity Welcomes Careful Drivers AND Better Than Life by Grant Naylor
Buy new: £9.47 / Used from: £0.01
Hilarious and surprisingly poignant story of the TV show
Guards! Guards! (Discworld)Guards! Guards! (Discworld) by Terry Pratchett
Buy new: £5.99 / Used from: £2.24
Not strictly sci-fi but in the same theme and still the best of the Discworld novels
Artemis Fowl: The Case So FarArtemis Fowl: The Case So Far by Eoin Colfer
Children's book it may be but it's also incredibly funny and very well plotted
Slaughterhouse 5, or The Children's Crusade - A Duty-dance with DeathSlaughterhouse 5, or The Children's Crusade - A Duty-dance with Death by Kurt Vonnegut
Buy new: £5.00 / Used from: £1.96
Funny, moving, depressing, daring. One of the classics of the 20th Century. So it goes.
Knees Up Mother Earth (Gollancz S.F.)Knees Up Mother Earth (Gollancz S.F.) by Robert Rankin
Buy new: £5.58 / Used from: £0.01
The best of Rankin's crazy, surreal stories
Soul PurposeSoul Purpose by Nick Marsh
Buy new: £13.99 / Used from: £1.78
James Herriot meets the X-files. Fantasticaly funny Douglas-Adams style story
Earth, Air, Fire and CustardEarth, Air, Fire and Custard by Tom Holt
Buy new: £6.39 / Used from: £0.01
Bizarre but funny third in Tom Holt's trilogy
Good OmensGood Omens by Neil Gaiman
Buy new: £5.98 / Used from: £0.01
Pratchett, Gaiman, and the end of the world. What more could you want?
ColonyColony by Rob Grant
Buy new: £7.19 / Used from: £0.01
Sci-Fi comedy from one-half of the Red Dwarf duo